View source for Glacier National Park (U.S.)

{{Short description|National park in Montana, United States}}
{{Distinguish|Glacier Bay National Park and Preserve}}
{{Use mdy dates|date=March 2021}}
{{Infobox protected area
| name = Glacier National Park
| iucn_category = II
| photo = Mountain Goat at Hidden Lake.jpg
| photo_caption = [[Mountain goat]], official park symbol, above Hidden Lake, with [[Dragons Tail (Montana)|Dragons Tail]] in the distance
| map = Montana#USA
| relief = 1
| map_caption = Location in Montana##Location in the United States
| label = Glacier National Park
| label_position = bottom
| mark = Red pog.svg
| marker_size = 7
| location = [[Flathead County, Montana|Flathead]] and [[Glacier County, Montana|Glacier]] counties, Montana, United States
| nearest_city =[[Columbia Falls, MT]]
| coordinates = {{Coord|48.7550|N|113.8000|W|format=dms|region:US-MT_type:landmark|display=inline, title}}
| area_acre = 1013322
| area_ref = <ref name="area">{{NPS area|year=2011|access-date=March 6, 2012}}</ref>
| established = {{start date and age|1910|05|11}}<ref>{{Cite web |title=History of Glacier National Park |url=https://www.montanapbs.org/programs/historyofglaciernationalpark/ |website=[[Montana PBS]] |access-date=May 8, 2020 |archive-date=June 28, 2022 |archive-url=https://web.archive.org/web/20220628143130/https://www.montanapbs.org/programs/historyofglaciernationalpark/ |url-status=live }}</ref>
| visitation_num = 2,908,458
| visitation_year = 2022
| visitation_ref = <ref>{{cite web |title=Annual Park Ranking Report for Recreation Visits in: 2022|url=https://irma.nps.gov/Stats/SSRSReports/National%20Reports/Annual%20Park%20Ranking%20Report%20(1979%20-%20Last%20Calendar%20Year) |website=nps.gov |publisher=National Park Service |access-date=July 23, 2023 }}</ref>
| governing_body = [[National Park Service]]
| website = {{URL|https://www.nps.gov/glac/index.htm}}
| embedded = {{Infobox UNESCO World Heritage Site
 |child = yes
 |Part_of = [[Waterton-Glacier International Peace Park]]
 |ID = 354
 |Year = 1995
 |Criteria = Natural: vii, ix
 }}
}}
'''Glacier National Park''' is a [[List of national parks of the United States|national park of the United States]] located in northwestern [[Montana]], on the [[Canada–United States border]]. The park encompasses more than {{convert|1.013|e6acre|km2|adj=ri0}} and includes parts of two mountain ranges (sub-ranges of the [[Rocky Mountains]]), more than 130 named lakes, more than 1,000 different [[species]] of plants, and hundreds of species of animals. This vast pristine [[ecosystem]] is the centerpiece of what has been referred to as the "Crown of the Continent Ecosystem", a region of protected land encompassing {{cvt|16000|mi2|km2}}.<ref name="crown">{{cite web |title=Welcome to the Crown of the Continent Ecosystem |publisher=Crown of the Continent Ecosystem Education Consortium |url=http://www.crownofthecontinent.org/coceec.htm |archive-url=https://web.archive.org/web/20120722094759/http://www.crownofthecontinent.org/coceec.htm |archive-date=July 22, 2012 |access-date=5 May 2022}}</ref>

The region that became Glacier National Park was first inhabited by [[Native Americans in the United States|Native Americans]]. Upon the arrival of European explorers, it was dominated by the [[Blackfoot Confederacy|Blackfeet]] in the east and the [[Confederated Salish and Kootenai Tribes of the Flathead Nation|Flathead]] in the western regions. Under pressure, the Blackfeet ceded the mountainous parts of their treaty lands in 1895 to the federal government which became part of the park. Soon after the establishment of the park on May 11, 1910, a number of hotels and chalets were constructed by the [[Great Northern Railway (U.S.)|Great Northern Railway]]. These historic hotels and chalets are listed as [[National Historic Landmarks]] and a total of 350 locations are on the [[National Register of Historic Places]]. By 1932 work was completed on the [[Going-to-the-Sun Road]], later designated a [[National Historic Civil Engineering Landmark]], which provided motorists easier access to the heart of the park.

Glacier National Park's mountains began forming {{Nowrap|170 million}} years ago when ancient rocks were forced eastward up and over much younger rock strata. Known as the [[Lewis Overthrust]], these sedimentary rocks are considered to have some of the finest examples of early life [[fossil]]s on Earth. The current shapes of the [[Lewis Range|Lewis]] and [[Livingston Range|Livingston]] mountain ranges and positioning and size of the lakes show the telltale evidence of massive glacial action, which carved U-shaped valleys and left behind moraines that impounded water, creating lakes. Of the estimated 150 [[Glacier|glaciers]] over {{convert|25| acres}} in size which existed in the park in the mid-19th century during the late [[Little Ice Age]], only 25 active glaciers remained by 2010.<ref name="Huffpo">{{Cite news |last=Brown |first=Matthew |title=2 more glaciers gone from Glacier National Park |newspaper=Huffington Post |date=April 7, 2010 |url=http://www.huffingtonpost.com/huff-wires/20100407/us-disappearing-glaciers/ |access-date=May 9, 2011 |archive-url=https://web.archive.org/web/20160310071330/http://www.huffingtonpost.com/huff-wires/20100407/us-disappearing-glaciers/ |archive-date=March 10, 2016 }}</ref> Scientists studying the glaciers in the park have estimated that all the active glaciers may disappear by 2030 if current climate patterns persist.<ref name="features"/>

Glacier National Park still maintains almost all of its modern, original native plant and animal species (since discovery by Europeans). Large mammals such as [[American black bear]], [[grizzly bear]], [[bighorn sheep]], [[Cervus canadensis|elk]], [[moose]], [[mountain lion]] and [[mountain goat]]s, as well as [[gray wolf]], [[wolverine]] and [[Canada lynx|Canadian lynx]] inhabit the park. Hundreds of species of birds, more than a dozen fish species, and quite a few reptiles and amphibian species have been documented. Species of butterflies, pollinating insects and other invertebrates range in the thousands.

The park has numerous ecosystems, ranging from [[prairie]] to [[tundra]]. The easternmost forests of [[Thuja plicata|western redcedar]] and [[Tsuga|hemlock]] grow in the southwest portion of the park. Forest fires are annually common in the park. There has been a fire every year of the park's existence except for in 1964. In total, 64 fires occurred in 1936 alone, the most on-record.<ref>{{Cite web |url=https://www.nps.gov/glac/learn/nature/fire-history.htm |title=Fire History – Glacier National Park |publisher=U.S. National Park Service |access-date=April 1, 2020 |archive-date=May 1, 2020 |archive-url=https://web.archive.org/web/20200501162632/https://www.nps.gov/glac/learn/nature/fire-history.htm |url-status=live }}</ref><ref>{{Cite web |url=https://nps.maps.arcgis.com/apps/PublicInformation/index.html?appid=9636385ceaa14684b099ac4759792a7e |title=Public Information Map |website=esri |access-date=April 1, 2020 |archive-date=June 11, 2021 |archive-url=https://web.archive.org/web/20210611150237/https://nps.maps.arcgis.com/apps/PublicInformation/index.html?appid=9636385ceaa14684b099ac4759792a7e |url-status=live }}</ref> In 2003, six fires burned approximately 136,000 acres (550&nbsp;km<sup>2</sup>), more than 13% of the park.<ref name="2003 fires">{{cite web |title=The Fires of 2003 |publisher=The Inside Trail: Voice of the Glacier Park Foundation |url=http://www.glacierparkfoundation.org/InsideTrail/IT_2004Win.pdf |date=Winter 2004 |access-date=April 1, 2020 |archive-date=September 18, 2020 |archive-url=https://web.archive.org/web/20200918070803/http://www.glacierparkfoundation.org/InsideTrail/IT_2004Win.pdf |url-status=live }}</ref>

Glacier National Park borders [[Waterton Lakes National Park]] in Canada—the two parks are known as the [[Waterton-Glacier International Peace Park]] and were designated as the world's first International Peace Park in 1932. Both parks were designated by the [[United Nations]] as [[Biosphere Reserve]]s in 1976, and in 1995 as [[World Heritage Site]]s.<ref name="UNESCO">{{cite web |title=Biosphere Reserve Information |publisher=United Nations Educational Scientific and Cultural Organization |url=http://www.unesco.org/mabdb/br/brdir/directory/biores.asp?code=USA+11&mode=all |date=March 11, 2005 |access-date=April 13, 2010 |archive-date=July 25, 2015 |archive-url=https://web.archive.org/web/20150725110933/http://www.unesco.org/mabdb/br/brdir/directory/biores.asp?mode=all&code=USA+11 |url-status=live }}</ref> In April 2017, the joint park received a provisional Gold Tier designation as Waterton-Glacier International Dark Sky Park through the [[International Dark Sky Association]],<ref>{{cite web |author1=Staff |title=2017 – Summer Guide to Waterton-Glacier International Peace Park |url=http://www.nps.gov/glac/upload/WGG-Web-2017.pdf |website=nps.gov |publisher=National Park Service |access-date=July 2, 2017 |page=1 |archive-date=June 17, 2019 |archive-url=https://web.archive.org/web/20190617200333/https://www.nps.gov/glac/upload/WGG-Web-2017.pdf }}</ref> the first transboundary [[dark sky park]].

==History==
[[File:BlackfeetatGlacier J.W.Schultz 1916 18 (border removed).JPG|thumb|[[Blackfoot Confederacy|Blackfeet]] camp at upper St. Mary Lake, {{circa|1916}}<ref>{{cite book |last=Schultz |first=James Willard |author-link=James Willard Schultz |title=Blackfeet Tales of Glacier National Park |publisher=Houghton, Mifflin & Co. |location=Boston |year=1916 |url=https://archive.org/details/blackfeettalesg00schugoog}}</ref>]]
The earliest occupants of the Glacier area with lineage to current tribes were the [[Confederated Salish and Kootenai Tribes of the Flathead Nation|Flathead (Salish) and Kootenai]],<ref>{{cite web |title=History & Culture |url=https://www.nps.gov/glac/learn/historyculture/index.htm |url-status=live |archive-url=https://web.archive.org/web/20220905161415/https://www.nps.gov/glac/learn/historyculture/index.htm |archive-date=September 5, 2022 |access-date=April 19, 2015 |publisher=National Park Service}}</ref> [[Shoshone]], and [[Cheyenne]]. The [[Blackfoot Confederacy|Blackfeet]] lived on the eastern slopes of what later became the park, as well as the [[Great Plains]] immediately to the east.<ref name="ait">{{cite web |title=American Indian Tribes |url=https://www.nps.gov/glac/learn/historyculture/tribes.htm |publisher=National Park Service |access-date=May 28, 2019 |date=June 18, 2016 |archive-date=May 28, 2019 |archive-url=https://web.archive.org/web/20190528203658/https://www.nps.gov/glac/learn/historyculture/tribes.htm |url-status=live }}</ref> The park region provided the Blackfeet shelter from the harsh winter winds of the plains, allowing them to supplement their traditional [[Bison hunting|bison hunt]]s with other game meat. The [[Blackfeet Indian Reservation]] borders the park in the east, while the [[Flathead Indian Reservation]] is located west and south of the park. When the Blackfeet Reservation was first established in 1855 by the Lame Bull Treaty, it included the eastern area of the current park up to the Continental Divide. To the Blackfeet, the mountains of this area, especially [[Chief Mountain]] and the region in the southeast at [[Two Medicine]], were considered the "Backbone of the World" and were frequented during [[vision quest]]s.<ref name="Blackfeet">{{cite book |last=Grinnell |first=George Bird |author-link=George Bird Grinnell |title=Blackfoot Lodge Tales |publisher=[[Charles Scribner's Sons]] |location=New York |year=1892 |url=http://www.gutenberg.org/ebooks/11547 |format=PDF |access-date=April 24, 2010 |isbn=978-0-665-06625-2 |archive-date=October 17, 2022 |archive-url=https://web.archive.org/web/20221017134204/https://www.gutenberg.org/ebooks/11547 |url-status=live }}</ref> In 1895 Chief White Calf of the Blackfeet authorized the sale of the mountain area, some {{cvt|800000|acre|km2|-2}}, to the U.S. government for {{Nowrap|$1.5 million}}, with the understanding that they would maintain usage rights to the land for hunting as long as the ceded strip will be "public land of the United States".<ref name="Spence">{{Cite book |last=Spence |first=Mark David |title=Dispossessing the Wilderness |url=https://archive.org/details/dispossessingwil00spen |url-access=limited |publisher=Oxford University Press |year=1999 |location=New York |isbn=978-0-19-514243-3 |page=[https://archive.org/details/dispossessingwil00spen/page/n90 80]}}</ref> This established the current boundary between the park and the reservation.<ref name="Weber 2019">{{cite web |last=Weber |first=Samantha |title=The Blackfeet Nation is opening its own national park |website=High Country News – Know the West |date=April 23, 2019 |url=https://www.hcn.org/articles/tribal-affairs-the-blackfeet-nation-is-trying-to-open-its-own-national-park |access-date=January 2, 2021 |archive-date=April 23, 2019 |archive-url=https://web.archive.org/web/20190423091812/https://www.hcn.org/articles/tribal-affairs-the-blackfeet-nation-is-trying-to-open-its-own-national-park |url-status=live }}</ref><ref name="UofMT">{{cite thesis |title=Blackfeet Agreement of 1895 and Glacier National Park |last=Ashby |first=Christopher S. |year=1985 |type=MS thesis |publisher=University of Montana |via=ScholarWorks |url=https://scholarworks.umt.edu/cgi/viewcontent.cgi?article=2703&context=etd |access-date=January 2, 2021 |archive-date=July 24, 2021 |archive-url=https://web.archive.org/web/20210724120255/https://scholarworks.umt.edu/cgi/viewcontent.cgi?article=2703&context=etd |url-status=live }}</ref>
{{quote box
 |title =
 |quote = Far away in northwestern Montana, hidden from view by clustering mountain peaks, lies an unmapped corner—the Crown of the Continent.
 |source = —'''George Bird Grinnell (1901)'''<ref name="Yenne">{{cite book |last=Yenne |first=Bill |title=Images of America-Glacier National Park |publisher=Arcadia Publications |location=Chicago, IL |year=2006 |isbn=978-0-7385-3011-6 |page=Introduction}}</ref>
 |align = left
 |width = 275px
 |border = 4px
 |fontsize = 125%
 |bgcolor = lightgrey
 |qalign = center
 |salign = center
}}

While exploring the [[Marias River]] in 1806, the [[Lewis and Clark Expedition]] came within {{cvt|50|mi|km|0}} of the area that is now the park.<ref>{{cite web |title=Early Settlers |url=https://www.nps.gov/glac/learn/historyculture/early-settlers.htm |publisher=National Park Service |access-date=May 28, 2019 |date=June 13, 2016 |archive-date=May 28, 2019 |archive-url=https://web.archive.org/web/20190528204139/https://www.nps.gov/glac/learn/historyculture/early-settlers.htm |url-status=live }}</ref> A series of explorations after 1850 helped to shape the understanding of the area that later became the park. In 1885 [[George Bird Grinnell]] hired the noted explorer (and later well-regarded author) [[James Willard Schultz]] to guide him on a hunting expedition into what would later become the park.<ref name="Hanna">{{cite book |last=Hanna |first=Warren L |title=The Life and Times of James Willard Schultz (Apikuni) |publisher=University of Oklahoma Press |location=Norman, Oklahoma |isbn=978-0-8061-1985-4 |chapter=Exploring With Grinnell |pages=[https://archive.org/details/lifetimesofjames0000hann/page/133 133–145] |year=1986 |chapter-url-access=registration |chapter-url=https://archive.org/details/lifetimesofjames0000hann/page/133}}</ref> After several more trips to the region, Grinnell became so inspired by the scenery that he spent the next two decades working to establish a national park. In 1901 Grinnell wrote a description of the region in which he referred to it as the "Crown of the Continent". His efforts to protect the land made him the premier contributor to this cause.<ref name="Century">{{Cite journal |last=Grinnell |first=George Bird |title=The Crown of the Continent |journal=The Century Magazine |volume=62 |pages=660–672 |date=May–October 1901 |url=https://books.google.com/books?id=WIPPAAAAMAAJ&q=The+crown+of+the+continent+in+Century+magazine&pg=PA660 |access-date=April 13, 2010 |archive-date=July 22, 2023 |archive-url=https://web.archive.org/web/20230722082522/https://books.google.com/books?id=WIPPAAAAMAAJ&q=The+crown+of+the+continent+in+Century+magazine&pg=PA660 |url-status=live }}</ref> A few years after Grinnell first visited, [[Henry L. Stimson]] and two companions, including a Blackfoot, climbed the steep east face of Chief Mountain in 1892.<ref name=Irma-NPS-gov>{{cite book |title=Glacier NP: Through The Years In Glacier National Park: An Administrative History |last=Robinson |first=Donald H. |url=https://irma.nps.gov/DataStore/DownloadFile/490209#page=20 |page=20 |date=May 1960 |publisher=Glacier Natural History Association, Inc.In Cooperatin with theNational Park Service |access-date=January 2, 2021}}</ref>

In 1891, the [[Great Northern Railway (U.S.)|Great Northern Railway]] crossed the Continental Divide at [[Marias Pass]] {{cvt|5213|ft|m|0}}, which is along the southern boundary of the park. In an effort to attract passengers, the Great Northern soon advertised the splendors of the region to the public. The company lobbied the [[United States Congress]]. In 1897 the park was designated as a forest preserve.<ref name="Spence2">{{Cite journal |last=Spence |first=Mark David |title=Crown of the Continent, Backbone of the World |journal=Environmental History |volume=1 |date=July 1996 |jstor=3985155 |issue=3 |pages=29–49 [35] |doi=10.2307/3985155 |s2cid=143232340}}{{registration required}}</ref> Under the forest designation, mining was still allowed but was not commercially successful. Meanwhile, proponents of protecting the region kept up their efforts. In 1910, under the influence of the [[Boone and Crockett Club]],<ref>{{cite book |last=Grinnell |first=George Bird |title=History of the Boone and Crockett Club |year=1910 |publisher=Forest and Stream Publishing Co. |location=New York, New York |page=9}}</ref> and spearheaded by [[George Bird Grinnell]] and [[Louis W. Hill]], president of the Great Northern, a bill was introduced into the U.S. Congress which designated the region a national park. This bill was signed into law by President [[William Howard Taft]] in 1910.<ref name="Centennial">{{cite web |title=People |publisher=National Park Service |url=https://www.nps.gov/glac/learn/historyculture/people.htm |date=August 22, 2016 |access-date=May 29, 2019 |archive-date=May 29, 2019 |archive-url=https://web.archive.org/web/20190529193448/https://www.nps.gov/glac/learn/historyculture/people.htm |url-status=live }}</ref> In 1910 Grinnell wrote, "This Park, the country owes to the Boone and Crockett Club, whose members discovered the region, suggested it being set aside, caused the bill to be introduced into congress and awakened interest in it all over the country".<ref>{{cite book |last=Grinnell |first=George Bird |title=The History of the Boone and Crockett Club |year=1910 |publisher=Forest and Stream Publishing Company |location=New York, New York |page=49}}</ref>

[[File:Many glacier hotel.jpg|thumb|[[Many Glacier Hotel]] on [[Swiftcurrent Lake]]]]
From May until August 1910, the forest reserve supervisor, Fremont Nathan Haines, managed the park's resources as the first acting superintendent. In August 1910, William Logan was appointed the park's first superintendent. While the forest reserve designation confirmed the traditional usage rights of the Blackfeet, the enabling legislation of the national park does not mention the guarantees to the Native Americans. The United States government's position was that with the special designation as a National Park the mountains ceded their multi-purpose ''public land status'' and the former rights ceased to exist as the Court of Claims confirmed it in 1935. Some Blackfeet held that their traditional usage rights still exist ''[[de jure]]''. In the 1890s, armed standoffs were avoided narrowly several times.<ref name="Spence3">{{Cite journal |last=Spence |first=Mark David |title=Crown of the Continent, Backbone of the World |journal=Environmental History |volume=1 |pages=40–41 |date=July 1996 |jstor=3985155 |issue=3 |doi=10.2307/3985155 |s2cid=143232340}}{{registration required}}</ref>

The Great Northern Railway, under the supervision of president [[Louis W. Hill]], built a number of hotels and [[chalet]]s throughout the park in the 1910s to promote tourism. These buildings, constructed and operated by a Great Northern subsidiary called the [[Glacier Park Company]], were modeled on Swiss architecture as part of Hill's plan to portray Glacier as "America's Switzerland". Hill was especially interested in sponsoring artists to come to the park, building tourist lodges that displayed their work. His hotels in the park never made a profit but they attracted thousands of visitors who came via the Great Northern.<ref>{{cite journal |last=Chacón |first=Hipólito Rafael |title=The Art of Glacier National Park |journal=Montana: The Magazine of Western History |date=Summer 2010 |volume=60 |issue=2 |pages=56–74 |publisher=Montana.gov}}</ref> Vacationers commonly took pack trips on horseback between the lodges or utilized the seasonal stagecoach routes to gain access to the [[Many Glacier]] areas in the northeast.<ref name="many">{{cite web |title=Many Glacier Hotel Historic Structure Report |publisher=National Park Service, U.S. Department of the Interior |url=http://www.nps.gov/archive/glac/pdf/mghiststr.pdf |archive-url=https://web.archive.org/web/20060921154716/http://www.nps.gov/archive/glac/pdf/mghiststr.pdf |archive-date=September 21, 2006 |date=July 2002 |access-date=April 13, 2010}}</ref>

[[File:St Mary Lake.jpg|thumb|left|upright=1.4|[[Saint Mary Lake]] and Wild Goose Island]]
The chalets, built between 1910 and 1915, included [[Belton Chalets|Belton]], St. Mary, Going-to-the-Sun, Many Glacier, Two Medicine, [[Sperry Chalet|Sperry]], [[Granite Park Chalet|Granite Park]], Cut Bank, and Gunsight Lake. The railway also built [[Glacier Park Lodge]], adjacent to the park on its east side, and the [[Many Glacier Hotel]] on the east shore of [[Swiftcurrent Lake]]. Louis Hill personally selected the sites for all of these buildings, choosing each for their dramatic scenic backdrops and views. Another developer, John Lewis, built the Lewis Glacier Hotel on [[Lake McDonald]] in 1913–1914. The Great Northern Railway bought the hotel in 1930 and it was later renamed [[Lake McDonald Lodge]].<ref name="lm">{{cite web |last=Harrison |first=Laura Soullière |title=Lake McDonald Lodge |work=Architecture in the Parks |publisher=National Park Service, U.S. Department of the Interior |year=2001 |url=http://www.nps.gov/history/history/online_books/harrison/harrison9.htm |access-date=April 13, 2010 |archive-date=May 14, 2013 |archive-url=https://web.archive.org/web/20130514052543/http://www.nps.gov/history/history/online_books/harrison/harrison9.htm }}</ref> The Great Northern Railway also established four tent camps at Red Eagle Lake, Cosley Lake, Fifty Mountain and Goat Haunt. The chalets and tent camps were located roughly 10–18 miles apart, and were connected by a network of trails that allowed visitors to tour Glacier's backcountry on foot or horseback. These trails were also constructed by the railroad. "Because of a lack of federal funds Great Northern assumed financial responsibility for all trail construction during this period, but was eventually reimbursed as funding became available."<ref>{{Cite book |last=Doran |first=Jeffrey J. |title=Ramble On: How Hiking Became One of the Most Popular Outdoor Activities in the World |year=2023 |isbn=979-8-3739-6392-3 |page=140|publisher=Amazon Digital Services LLC - Kdp }}</ref> Today, only Sperry, Granite Park, and Belton Chalets are still in operation, while a building formerly belonging to Two Medicine Chalet is now [[Two Medicine Store]].<ref name="Djuff">{{cite book |last=Djuff |first=Ray |title=View with a Room: Glacier's Historic Hotels and Chalets |publisher=Farcountry Press |location=Helena, Montana |year=2001 |isbn=978-1-56037-170-0 |page=52}}</ref> The surviving chalet and hotel buildings within the park are now designated as [[National Historic Landmarks]].<ref name="gn">{{cite web |last=Harrison |first=Laura Soullière |title=Great Northern Railway Buildings |work=Architecture in the Parks |publisher=National Park Service, U.S. Department of the Interior |year=1986 |url=http://www.cr.nps.gov/history/online_books/harrison/harrison8.htm |access-date=April 13, 2010 |archive-url=https://web.archive.org/web/20060417205802/http://www.cr.nps.gov/history/online_books/harrison/harrison8.htm |archive-date=April 17, 2006}}</ref> In total, 350 buildings and structures within the park are listed on the [[National Register of Historic Places]], including ranger stations, backcountry patrol cabins, fire lookouts, and concession facilities.<ref name="management1">{{cite web |title=General Management Plan |publisher=National Park Service, U.S. Department of the Interior |date=April 1999 |page=49 |url=http://www.nps.gov/archive/glac/pdf/gmpfinal.pdf |archive-url=https://web.archive.org/web/20070127084050/http://www.nps.gov/archive/glac/pdf/gmpfinal.pdf |archive-date=January 27, 2007 |access-date=April 14, 2010}}</ref> In 2017, Sperry Chalet closed early for the season due to the [[Sprague Fire]] which subsequently burned the entire interior portions of the structure, leaving only the stone exterior standing. Due to damage, the chalet was closed indefinitely and while the exterior stonework was stabilized in the fall of 2017.<ref name=Backus>{{cite web |last1=Backus |first1=Perry |title=Glacier Park plans to begin stabilization efforts on Sperry Chalet in October |url=http://missoulian.com/news/local/glacier-park-plans-to-begin-stabilization-efforts-on-sperry-chalet/article_d47b2a89-8e93-55b1-9172-9b0639d56423.html |website=missoulian.com |access-date=October 31, 2017 |language=en |date=September 25, 2017 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154425/https://missoulian.com/news/local/glacier-park-plans-to-begin-stabilization-efforts-on-sperry-chalet/article_d47b2a89-8e93-55b1-9172-9b0639d56423.html |url-status=live }}</ref> The rebuilding process was completed during the summers of 2018 and 2019,<ref>{{cite web |title=Sperry Chalet Environmental Assessment Complete |url=https://www.nps.gov/glac/learn/news/18-17.htm |publisher=National Park Service |access-date=June 6, 2018 |date=May 17, 2018 |archive-date=July 22, 2023 |archive-url=https://web.archive.org/web/20230722082547/https://www.nps.gov/glac/learn/news/18-17.htm |url-status=live }}</ref> and a reopening ceremony was held in February 2020.<ref name="Wells">{{cite web |last1=Wells |first1=Sean |title=Glacier National Park officials celebrate reopening of Sperry Chalet |url=https://www.kpax.com/news/local-news/flathead-county/glacier-national-park-officials-celebrate-reopening-of-sperry-chalet |access-date=April 2, 2020 |date=February 26, 2020 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154425/https://www.kpax.com/news/local-news/flathead-county/glacier-national-park-officials-celebrate-reopening-of-sperry-chalet |url-status=live }}</ref>

[[File:Going to the Sun Mountain 1932.jpg|thumb|Road construction along the [[Going-to-the-Sun Road]] with [[Going-to-the-Sun Mountain]] in the background, 1932]]
After the park was well established and visitors began to rely more on automobiles, work was begun on the {{convert|53|mi|km|0|adj=on}} long [[Going-to-the-Sun Road]], completed in 1932. Also known simply as the Sun Road, the road bisects the park and is the only route that ventures deep into the park, going over the Continental Divide at [[Logan Pass]], {{cvt|6646|ft|m|0}} at the midway point. The Sun Road is also listed on the National Register of Historic Places and in 1985 was designated a [[National Historic Civil Engineering Landmark]].<ref name="Guthrie">{{cite book |last=Guthrie |first=C. W. |title=Going-To-The-Sun Road: Glacier National Park's Highway to the Sky |publisher=Farcountry Press |location=Helena, Montana |year=2006 |isbn=978-1-56037-335-3 |page=8}}</ref> Another route, along the southern boundary between the park and [[United States National Forest|National Forests]], is [[U.S. Route 2 in Montana|US Route 2]], which crosses the Continental Divide at Marias Pass and connects the towns of West Glacier and [[East Glacier Park Village, Montana|East Glacier]].<ref name="GNP 2020" />

The [[Civilian Conservation Corps]] (CCC), a [[New Deal]] relief agency for young men, played a major role between 1933 and 1942 in developing both Glacier National Park and Yellowstone National Park. CCC projects included reforestation, campground development, trail construction, fire hazard reduction, and fire-fighting work.<ref>Matthew A. Redinger, "The Civilian Conservation Corps and the Development of Glacier and Yellowstone Parks, 1933–1942," ''Pacific Northwest Forum,'' 1991, Vol. 4 Issue 2, pp 3–17</ref> The increase in motor vehicle traffic through the park during the 1930s resulted in the construction of new concession facilities at [[Swiftcurrent Auto Camp Historic District|Swiftcurrent]] and [[Rising Sun (Montana)|Rising Sun]], both designed for automobile-based tourism. These early auto camps are now also listed on the National Register.<ref name="Djuff"/>

==Park management==
[[File:GlacierNP L7 20010701.jpg|thumb|[[Landsat 7]] image of [[Waterton-Glacier International Peace Park]]. The [[Rocky Mountain Front]] formed by the [[Lewis Overthrust]] fault rises dramatically above the Great Plains on the right.]]
Glacier National Park is managed by the [[National Park Service]], with the park's headquarters in West Glacier, Montana. Visitation to Glacier National Park averaged about {{Nowrap|3.5 million}} visitors in 2019, which surpassed its 2017 peak of {{Nowrap|3.31 million}}.<ref name=summary>{{cite web |title=Stats Report Viewer |website=irma.nps.gov |url=https://irma.nps.gov/Stats/SSRSReports/Park%20Specific%20Reports/Summary%20of%20Visitor%20Use%20By%20Month%20and%20Year%20(1979%20-%20Last%20Calendar%20Year)?Park=GLAC |access-date=January 2, 2021 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154430/https://irma.nps.gov/STATS/SSRSReports/Park%20Specific%20Reports/Summary%20of%20Visitor%20Use%20By%20Month%20and%20Year%20%281979%20-%20Last%20Calendar%20Year%29?Park=GLAC |url-status=live }}</ref><ref name="visits">{{NPS Visitation|access-date=March 7, 2019}}</ref> Glacier has had at least 2 million annual visitors consistently since 2012, but has broken annual attendance records from 2014 to 2018.<ref name="Flathead Beacon 2018">{{cite web |title=Glacier Park Sees Second Busiest July on Record |website=Flathead Beacon |date=August 14, 2018 |url=https://flatheadbeacon.com/2018/08/14/glacier-park-sees-second-busiest-july-record/ |access-date=January 2, 2021 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154425/https://flatheadbeacon.com/2018/08/14/glacier-park-sees-second-busiest-july-record/ |url-status=live }}</ref>

In anticipation of the 100th anniversary of the park in 2010, major reconstruction of the Going-to-the-Sun Road was completed. The [[Federal Highway Administration]] managed the reconstruction project in cooperation with the National Park Service.<ref name="FHA">{{cite web |title=Going-to-the-Sun Road project |publisher=U.S. Department of Transportation |date=April 14, 2010 |url=https://highways.dot.gov/federal-lands/projects |access-date=April 14, 2010 |url-status=live |archive-url=https://web.archive.org/web/20100401190819/http://www.wfl.fhwa.dot.gov/projects/gtsr/ |archive-date=April 1, 2010}}</ref> Some rehabilitation of major structures such as visitor centers and historic hotels, as well as improvements in wastewater treatment facilities and campgrounds, were expected to be completed by the anniversary date.<ref>{{cite book |title=Department of the Interior and Related Agencies Appropriations for 2005: Hearings Before a Subcommittee of the Committee on Appropriations, House of Representatives, One Hundred Eighth Congress, Second Session |publisher=U.S. Government Printing Office |issue=v. 1 |year=2004 |isbn=978-0-16-069712-8 |url=https://books.google.com/books?id=t0ceAAAAMAAJ&pg=PA1810 |access-date=January 2, 2021 |page=1810 |archive-date=July 22, 2023 |archive-url=https://web.archive.org/web/20230722082522/https://books.google.com/books?id=t0ceAAAAMAAJ&pg=PA1810 |url-status=live }}</ref> The National Park Service engaged in fishery studies for Lake McDonald to assess status and develop protection programs to enhance native fish populations.<ref name="Glacier National Park-2018">{{cite web |title=Fishing |website=Glacier National Park (U.S. National Park Service) |date=October 11, 2018 |url=https://www.nps.gov/glac/planyourvisit/fishing.htm |access-date=January 2, 2021 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154432/https://www.nps.gov/glac/planyourvisit/fishing.htm |url-status=live }}</ref> The restoration of park trails, education and youth programs, park improvements and many community programs were also planned.<ref>{{cite web |title=Park-Current-Projects |website=Glacier National Park Conservancy |date=October 29, 2020 |url=https://glacier.org/park-current-projects/ |access-date=January 2, 2021 |archive-date=September 2, 2022 |archive-url=https://web.archive.org/web/20220902055350/https://glacier.org/park-current-projects/ |url-status=live }}</ref>

The National Park Service mandate is to "...&nbsp;preserve and protect natural and cultural resources". The [[Organic Act]] of August 25, 1916 established the National Park Service as a federal agency. One major section of the Act has often been summarized as the "Mission", "...&nbsp;to promote and regulate the use of the&nbsp;... national parks&nbsp;... which purpose is to conserve the scenery and the natural and historic objects and the wildlife therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations."<ref name="mission">{{cite web |title=The National Park System, Caring for the American Legacy |publisher=National Park Service, U.S. Department of the Interior |url=http://www.nps.gov/legacy/mission.html |access-date=April 14, 2010 |archive-date=March 5, 2012 |archive-url=https://web.archive.org/web/20120305215556/http://www.nps.gov/legacy/mission.html }}</ref> In keeping with this mandate, hunting is illegal in the park, as are [[mining]], [[forestry|logging]], and the removal of natural or cultural resources. Additionally, [[oil exploration|oil]] and [[Natural gas|gas exploration]] and extraction are not permitted. These restrictions caused a lot of conflict with the adjoining Blackfeet Indian Reservation. When they sold the land to the United States government, it was with the stipulation of being able to maintain their usage rights of the area, many of which (such as hunting) had come into conflict with these regulations.<ref name="Spence"/>

In 1974, a [[wilderness]] study was submitted to Congress which identified 95% of the area of the park as qualifying for wilderness designation. Unlike a few other parks, Glacier National Park has yet to be protected as wilderness, but National Park Service policy requires that identified areas listed in the report be managed as wilderness until Congress renders a full decision.<ref name="management1"/> Ninety-three percent of Glacier National Park is managed as wilderness, even though it has not been officially designated.<ref name="mammals">{{cite web |title=Mammals |publisher=National Park Service |url=https://www.nps.gov/glac/learn/nature/mammals.htm |date=March 5, 2008 |access-date=April 18, 2010 |archive-date=July 13, 2013 |archive-url=https://web.archive.org/web/20130713130639/http://www.nps.gov/glac/naturescience/mammals.htm |url-status=live }}</ref>{{Failed verification|date=July 2025}}

==Geography and geology==
{{Main list|List of mountains and mountain ranges of Glacier National Park (U.S.)}}
[[File:Winter on the Flathead River.jpg|thumb|Winter on the [[Flathead River]]]]
[[File:Glac cross section en.svg|thumb|upright=1.7|Geological cross section of Glacier National Park (U.S.)]]
The park is bordered on the north by Waterton Lakes National Park in Alberta, and the Flathead Provincial Forest and [[Akamina-Kishinena Provincial Park]] in British Columbia.<ref name="Akamina">{{cite web |title=Akamina-Kishinena Provincial Park |publisher=BC Parks |url=http://www.env.gov.bc.ca/bcparks/explore/parkpgs/akamina/ |access-date=April 19, 2010 |archive-date=March 3, 2016 |archive-url=https://web.archive.org/web/20160303220507/http://www.env.gov.bc.ca/bcparks/explore/parkpgs/akamina/ |url-status=live }}</ref> To the west, the north fork of the [[Flathead River]] forms the western boundary, while its middle fork is part of the southern boundary. The Blackfeet Indian Reservation provides most of the eastern boundary. The [[Lewis and Clark National Forest|Lewis and Clark]] and the [[Flathead National Forest]]s form the southern and western boundary.<ref name="reservation">{{cite web |title=Nearby Attractions |publisher=National Park Service |url=https://www.nps.gov/glac/planyourvisit/nearbyattractions.htm |date=January 11, 2010 |access-date=April 19, 2010 |archive-date=March 17, 2013 |archive-url=https://web.archive.org/web/20130317074035/http://www.nps.gov/glac/planyourvisit/nearbyattractions.htm |url-status=live }}</ref> The remote [[Bob Marshall Wilderness Complex]] is located in the two forests immediately to the south.<ref name="bob">{{cite web |title=Great Bear Wilderness |publisher=Wilderness.net, The University of Montana |url=http://www.wilderness.net/index.cfm?fuse=NWPS&sec=wildView&WID=219 |access-date=April 19, 2010 |archive-url=https://web.archive.org/web/20100612003218/http://wilderness.net/index.cfm?fuse=NWPS&sec=wildView&WID=219 |archive-date=June 12, 2010 }}</ref>

The park contains over 700 lakes, but only 131 have been named as of 2016.<ref name="lakes">{{cite web |title=Lakes and Ponds |work=Nature and Science |publisher=National Park Service |url=https://www.nps.gov/glac/learn/nature/lakesandponds.htm |date=June 19, 2016 |access-date=March 4, 2021 |archive-date=March 30, 2013 |archive-url=https://web.archive.org/web/20130330063403/http://www.nps.gov/glac/naturescience/lakesandponds.htm |url-status=live }}</ref> Lake McDonald on the western side of the park is the longest at {{convert|10|mi|km}} and the deepest at {{convert|464|ft|m}}. Numerous smaller lakes, known as [[tarn (lake)|tarn]]s, are located in [[cirque (landform)|cirque]]s formed by glacial erosion. Some of these lakes, like [[Avalanche Lake (Flathead County, Montana)|Avalanche Lake]] and [[Cracker Lake]], are colored an opaque turquoise by suspended glacial [[silt]], which also causes a number of streams to run milky white. Glacier National Park lakes remain cold year-round, with temperatures rarely above {{convert|50|°F|°C|0}} at their surface.<ref name="lakes"/> Cold water lakes such as these support little [[plankton]] growth, ensuring that the lake waters are remarkably clear. However, the lack of plankton lowers the rate of pollution filtration, so pollutants tend to linger longer. Consequently, the lakes are considered environmental [[Bellwether (politics)|bellwether]]s as they can be quickly affected by even minor increases in pollutants.<ref name="pollution">{{cite web |title=WACAP&nbsp;– Western Airborne Contaminants Assessment Project |publisher=National Park Service |url=http://www.nature.nps.gov/air/studies/air_toxics/wacap.cfm#Database |date=February 25, 2010 |access-date=April 19, 2010 |archive-date=February 15, 2013 |archive-url=https://web.archive.org/web/20130215121455/http://www2.nature.nps.gov/air/Studies/air_toxics/wacap.cfm#Database }}</ref>

Two hundred waterfalls are scattered throughout the park. However, during drier times of the year, many of these are reduced to a trickle. The largest falls include those in the [[Two Medicine]] region, McDonald Falls in the McDonald Valley, and Swiftcurrent Falls in the [[Many Glacier]] area, which is easily observable and close to the Many Glacier Hotel. One of the tallest waterfalls is [[Bird Woman Falls]], which drops {{convert|492|ft|m}} from a hanging valley beneath the north slope of [[Mount Oberlin]].<ref name="birdwoman">{{cite web |title=Bird Woman Falls |publisher=World Waterfall Database |url=http://www.world-waterfalls.com/waterfall.php?num=493 |date=September 13, 2005 |access-date=April 21, 2010 |archive-url=https://web.archive.org/web/20100105143147/http://world-waterfalls.com/waterfall.php?num=493 |archive-date=January 5, 2010}}</ref>

===Geology===
{{Multiple image|total_width=230|align=left|direction=vertical
|image1=Two Medicine Lake.jpg|caption1=[[Two Medicine Lake]] and [[Sinopah Mountain]]
|image2=Stromatolites, Belt Supergroup, Glacier National Park.jpg|caption2=[[Stromatolite]]s, [[Belt Supergroup]], dated to the [[Mesoproterozoic|Mesoproterozoic Era]], ~1.44 billion years ago; polished slab at the [[Museum of the Rockies]]
}}
The rocks found in the park are primarily [[sedimentary rock]]s of the [[Belt Supergroup]]. They were deposited in shallow seas over 1.6&nbsp;billion to 800&nbsp;million years ago. During the formation of the [[Rocky Mountains]] 170&nbsp;million years ago, one region of rocks now known as the Lewis Overthrust was forced eastward {{convert|50|mi|km|0}}. This [[Thrust fault|overthrust]] was several miles (kilometers) thick and hundreds of miles (kilometers) long.<ref name="geology">{{cite web |title=Lewis Overthrust Fault |publisher=National Park Service, U.S. Department of the Interior |url=https://www.nps.gov/glac/learn/nature/geology.htm |access-date=September 3, 2010 |archive-date=May 22, 2013 |archive-url=https://web.archive.org/web/20130522022344/http://nature.nps.gov/geology/parks/glac/index.cfm |url-status=live }}</ref> This resulted in older rocks being displaced over newer ones, so the overlying [[Proterozoic]] rocks are between 1.4 and 1.5&nbsp;billion years older than [[Cretaceous]] age rocks they now rest on.<ref name="geology"/><ref name="fieldnotes">{{cite web |title=Park Geology |work=Geology Fieldnotes |publisher=National Park Service, U.S. Department of the Interior |url=https://www.nps.gov/subjects/geology/geologic-tour.htm |date=January 4, 2005 |access-date=April 21, 2010 |archive-date=May 8, 2013 |archive-url=https://web.archive.org/web/20130508152512/http://www.nature.nps.gov/geology/parks/glac/ |url-status=live}}</ref>

One of the most dramatic evidences of this overthrust is visible in the form of Chief Mountain, an isolated peak on the edge of the eastern boundary of the park rising {{convert|2500|ft|m|-2}} above the Great Plains.<ref name="fieldnotes"/><ref name="formations">{{cite web |title=Geologic Formations |work=Nature and Science |publisher=National Park Service |url=https://www.nps.gov/glac/learn/nature/geologicformations.htm |date=March 29, 2008 |access-date=April 21, 2010 |archive-date=April 13, 2013 |archive-url=https://web.archive.org/web/20130413173133/http://www.nps.gov/glac/naturescience/geologicformations.htm |url-status=live }}</ref> There are six mountains in the park over {{convert|10000|ft|m|-2}} in elevation, with [[Mount Cleveland (Montana)|Mount Cleveland]] at {{convert|10466|ft|m|0}} being the tallest.<ref name="peaks">{{cite peakbagger |rid=1421 |name=Glacier National Park Ranges |access-date=April 21, 2010}}</ref> Appropriately named [[Triple Divide Peak (Montana)|Triple Divide Peak]] sends waters towards the Pacific Ocean, [[Hudson Bay]], and [[Gulf of Mexico]] [[drainage basin|watershed]]s. This peak can effectively be considered to be the apex of the North American continent, although the mountain is only {{convert|8020|ft|m|0}} above sea level.<ref name="triple">{{cite peakbagger |pid=4815 |name=Triple Divide Peak, Montana |access-date=April 21, 2010}}</ref>

The rocks in Glacier National Park are the best preserved Proterozoic sedimentary rocks in the world, with some of the world's most fruitful sources for records of early life. Sedimentary rocks of similar age located in other regions have been greatly altered by mountain building and other metamorphic changes; consequently, fossils are less common and more difficult to observe.<ref name="sedimentary">{{cite web |title=Exposed Rocks within the Park |work=America's Volcanic Past: Montana |publisher=United States Geological Survey |url=https://vulcan.wr.usgs.gov/LivingWith/VolcanicPast/Places/volcanic_past_montana.html |date=June 11, 2003 |access-date=April 24, 2010 |archive-url=https://web.archive.org/web/20100619063033/http://vulcan.wr.usgs.gov/LivingWith/VolcanicPast/Places/volcanic_past_montana.html |archive-date=June 19, 2010}}</ref> The rocks in the park preserve such features as millimeter-scale lamination, ripple marks, mud cracks, salt-crystal casts, raindrop impressions, [[oolite]]s, and other sedimentary bedding characteristics. Six fossilized species of [[stromatolite]]s, early organisms consisting of primarily blue-green [[algae]], have been documented and dated at about 1&nbsp;billion years.<ref name="formations"/> The discovery of ''[[Horodyskia]]'' within the [[Appekunny Formation]], a well-preserved rock stratum in the park, pushed back the established date for the origination of eukaryotic life a full billion years.<ref name="fieldnotes"/>

===Glaciers===
{{Main|Glaciers in Glacier National Park (U.S.)}}
[[File:USGSglacierssince1850.jpg|thumb|upright=1.3|Glacial retreat since the end of the [[Little Ice Age]] in 1850]]
Glacier National Park is dominated by mountains which were carved into their present shapes by the huge glaciers of the [[last glacial maximum|last ice age]]. These glaciers have largely disappeared over the last 12,000 years.<ref name="ice age">{{cite web |title=History of Glaciers in Glacier National Park |publisher=Northern Rocky Mountain Science Center, United States Geological Survey |url=https://www.nrmsc.usgs.gov/research/climate_glaciers.htm |date=April 13, 2010 |access-date=April 24, 2010 |archive-url=https://web.archive.org/web/20100529193154/http://www.nrmsc.usgs.gov/research/climate_glaciers.htm |archive-date=May 29, 2010}}</ref> Evidence of widespread glacial action is found throughout the park in the form of [[U-shaped valley]]s, [[cirque]]s, [[arête]]s, and large outflow lakes radiating like fingers from the base of the highest peaks.<ref name="features">{{cite web |title=Glaciers / Glacial Features |publisher=National Park Service |url=http://www.nps.gov/glac/naturescience/glaciers.htm |date=October 6, 2014 |access-date=January 2, 2020 |archive-url=https://web.archive.org/web/20141014234242/http://www.nps.gov/glac/naturescience/glaciers.htm |archive-date=October 14, 2014 }}</ref> Since the end of the ice ages, various warming and cooling trends have occurred. The last recent cooling trend was during the Little Ice Age, which took place approximately between 1550 and 1850.<ref name="change">{{cite web |title=Was there a Little Ice Age and a Medieval Warm Period? |publisher=Intergovernmental Panel on Climate Change, United Nations Environment Programme |url=http://www.grida.no/climate/ipcc_tar/wg1/070.htm |year=2003 |access-date=April 24, 2010 |archive-url=https://web.archive.org/web/20060529044319/http://www.grida.no/climate/ipcc_tar/wg1/070.htm |archive-date=May 29, 2006}}</ref> During the Little Ice Age, the glaciers in the park expanded and advanced, although to nowhere near as great an extent as they had during the Ice Age.<ref name="ice age"/>

During the middle of the 20th century, examining the maps and photographs from the previous century provided clear evidence that the 150 glaciers known to have existed in the park a hundred years earlier had greatly retreated and disappeared altogether in many cases.<ref name="retreat">{{cite web |title=Retreat of Glaciers in Glacier National Park |publisher=Northern Rocky Mountain Science Center, United States Geological Survey |url=https://www.nrmsc.usgs.gov/research/glacier_retreat.htm |date=April 13, 2010 |access-date=April 24, 2010 |archive-url=https://web.archive.org/web/20100528045410/http://www.nrmsc.usgs.gov/research/glacier_retreat.htm |archive-date=May 28, 2010 }}</ref> Repeat photography of the glaciers, such as the pictures taken of [[Grinnell Glacier]] between 1938 and 2015 as shown, help to provide visual confirmation of the extent of glacier retreat.<ref name="USGS.gov 2017">{{cite web |title=Time Series of Glacier Retreat |website=USGS.gov |date=May 15, 2017 |url=https://www.usgs.gov/centers/norock/science/time-series-glacier-retreat?qt-science_center_objects=0#qt-science_center_objects |access-date=January 2, 2021 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154431/https://www.usgs.gov/centers/norock/science/time-series-glacier-retreat?qt-science_center_objects=0#qt-science_center_objects |url-status=live }}</ref>

{| class="center toccolours"
|+ '''Grinnell Glacier over time'''
|<gallery mode="packed" heights="150" style="line-height:150%">
File:Grinnell Glacier 1938.jpg|1938
File:Grinnell Glacier 1981.jpg|1981
File:Grinnell Glacier 1998.jpg|1998
File:Grinnell Glacier 2009.jpg|2009
File:Grinnell Glacier from summit of Mt Gould 2015 7648 crop.jpg|2015
File: Grinnell Glacier from Mount Gould in 2019 (54209702469).jpg|2019
File: Grinnell Glacier from Mount Gould in 2021 (54209695438).jpg|2021
</gallery>
|}

In the 1980s, the [[U.S. Geological Survey]] began a more systematic study of the remaining glaciers, which has continued to the present day. By 2010, 37 glaciers remained, but only 25 of them were at least {{cvt|25|acre|km2}} in area and therefore still considered active.<ref name="Huffpo"/><ref name="retreat"/> Based on the warming trend of the early 2000s, scientists had estimated that the park's remaining glaciers would melt by 2020;<ref>{{Cite web |url=http://www.nps.gov/glac/naturescience/glaciers.htm |title=Glaciers/Glacial Features |date=September 22, 2009 |website=National Park Service |archive-url=https://web.archive.org/web/20100228131102/http://www.nps.gov/glac/naturescience/glaciers.htm |archive-date=February 28, 2010 |access-date=January 2, 2020}}</ref> however, a later estimate stated that the glaciers may be gone by 2030.<ref name="features"/> This [[retreat of glaciers since 1850|glacier retreat]] follows a worldwide pattern that has accelerated even more since 1980. Without a major climatic change in which cooler and moister weather returns and persists, the [[Glacier mass balance|mass balance]], which is the accumulation rate versus the ablation (melting) rate of glaciers, will continue to be negative and the glaciers have been projected to disappear, leaving behind only barren rock eventually.<ref name="monitoring">{{cite web |title=Monitoring and Assessing Glacier Changes and Their Associated Hydrologic and Ecologic Effects in Glacier National Park |work=Glacier Monitoring Research |publisher=Northern Rocky Mountain Science Center, United States Geological Survey |url=https://www.nrmsc.usgs.gov/research/glaciers.htm |date=April 13, 2010 |access-date=April 24, 2010 |archive-url=https://web.archive.org/web/20130218164617/http://www.nrmsc.usgs.gov/research/glaciers.htm |archive-date=February 18, 2013}}</ref>

After the end of the Little Ice Age in 1850, the glaciers in the park retreated moderately until the 1910s. Between 1917 and 1941, the retreat rate accelerated and was as high as {{convert|330|ft|m}} per year for some glaciers.<ref name="retreat"/> A slight cooling trend from the 1940s until 1979 helped to slow the rate of retreat and, in a few cases, even advanced the glaciers over ten meters. However, during the 1980s, the glaciers in the park began a steady period of loss of glacial ice, which continues as of 2010. In 1850, the glaciers in the region near [[Blackfoot Glacier|Blackfoot]] and [[Jackson Glacier]]s covered {{convert|5337|acre|km2|1}}, but by 1979, the same region of the park had glacier ice covering only {{convert|1828|acre|km2|1}}. Between 1850 and 1979, 73% of the glacial ice had melted away.<ref name="hall">{{cite journal |last=Hall |first=Myrna |author2=Daniel Fagre |title=Modeled Climate-Induced glacier change in Glacier National Park, 1850–2100 |volume=53 |issue=2 |journal=BioScience |date=February 2003 |page=131 |doi=10.1641/0006-3568(2003)053[0131:MCIGCI]2.0.CO;2 |doi-access=free}}</ref> At the time the park was created, Jackson Glacier was part of Blackfoot Glacier, but the two have separated into individual glaciers since.<ref name="jackson">{{cite web |title=Blackfoot-Jackson Glacier Complex 1914–2009 |publisher=Northern Rocky Mountain Science Center, United States Geological Survey |url=https://www.nrmsc.usgs.gov/repeatphoto/blackfoot.htm |date=April 13, 2010 |access-date=April 24, 2010 |archive-url=https://web.archive.org/web/20100527210707/http://www.nrmsc.usgs.gov/repeatphoto/blackfoot.htm |archive-date=May 27, 2010}}</ref>

It is unknown how glacial retreat may affect the park's ecosystems beyond the broad concept of creating new problems over time, and intensifying or exacerbating existing challenges.<ref name="GNP–2018">{{cite web |title=Climate Change |website=Glacier National Park (U.S. National Park Service) |date=2018-08-12 |url=https://www.nps.gov/glac/learn/nature/climate-change.htm |access-date=2022-02-06 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154432/https://www.nps.gov/glac/learn/nature/climate-change.htm |url-status=live }}</ref> There is concern over negative impacts, such as the loss of habitat for plant and animal species that are dependent on cold water. Less glacial melt reduces stream level flow during the dry summer and fall seasons, and lowers water table levels overall, increasing the risk of forest fires. The loss of glaciers will also reduce the aesthetic appeal that glaciers provide to visitors.<ref name="hall"/> Relative to the unpredictability of emerging science, misinformation began to circulate in the news media and on social media in early to mid-2019, claiming that the Park Service had discreetly removed or changed placards, movies, brochures, and other literature warning that the park's glaciers would be gone by 2020.<ref name="Iowa Climate Science Education 2019">{{cite web |title=Glacier National Park Quietly Removes Its 'Gone by 2020' Signs |website=Iowa Climate Science Education |date=2019-06-06 |url=https://iowaclimate.org/2019/06/06/glacier-national-park-quietly-removes-its-gone-by-2020-signs/ |access-date=2022-02-06 |archive-date=February 6, 2022 |archive-url=https://web.archive.org/web/20220206234435/https://iowaclimate.org/2019/06/06/glacier-national-park-quietly-removes-its-gone-by-2020-signs/ |url-status=live }}</ref><ref name="Maxouris Rose 2020">{{cite web |last1=Maxouris |first1=Christina |last2=Rose |first2=Andy |title=Montana park is replacing signs that predicted its glaciers would be gone by 2020 |website=CTVNews |date=2020-01-09 |url=https://www.ctvnews.ca/world/article/montana-park-is-replacing-signs-that-predicted-its-glaciers-would-be-gone-by-2020/ |access-date=2022-02-06 |archive-date=February 6, 2022 |archive-url=https://web.archive.org/web/20220206235647/https://www.ctvnews.ca/world/montana-park-is-replacing-signs-that-predicted-its-glaciers-would-be-gone-by-2020-1.4759675 |url-status=live }}</ref> Apparently, the event was triggered when the Park Service began updating their on-site placards to reflect the latest scientific findings. The "gone by 2020" date on one placard was replaced with, "When they will completely disappear, however, depends on how and when we act." Another placard states, "Some glaciers melt faster than others, but one thing is consistent: the glaciers in the park are shrinking."<ref>{{cite web |title=Fact check: No, the glaciers are not growing in Glacier National Park » Yale Climate Connections |website=Yale Climate Connections |date=2019-09-13 |url=http://yaleclimateconnections.org/2019/09/fact-check-no-the-glaciers-are-not-growing-in-glacier-national-park/ |access-date=2022-02-06 |archive-date=October 17, 2022 |archive-url=https://web.archive.org/web/20221017023230/https://yaleclimateconnections.org/2019/09/fact-check-no-the-glaciers-are-not-growing-in-glacier-national-park/ |url-status=live }}</ref>

===Climate===
[[File:Big Drift.jpg|thumb|The [[Big Drift]] covering the Going-to-the-Sun Road on March 23, 2006]]
As the park spans the Continental Divide, and has more than {{convert|7000|ft|m}} in elevation variance, many climates and [[microclimate]]s are found in the park. As with other alpine systems, average temperature usually drops as elevation increases.<ref name="montane">{{cite web |title=Montane Forest Ecotype |publisher=State of Montana |url=http://fwpiis.mt.gov/content/getItem.aspx?id=26470 |access-date=April 18, 2010 |archive-url=https://web.archive.org/web/20100420030551/http://fwpiis.mt.gov/content/getItem.aspx?id=26470 |archive-date=April 20, 2010}}</ref> The western side of the park, in the Pacific watershed, has a milder and wetter climate, due to its lower elevation. Precipitation is greatest during the winter and spring, averaging {{convert|2|to|3|in|mm|-1}} per month. Snowfall can occur at any time of the year, even in the summer, and especially at higher altitudes. The winter can bring prolonged cold waves, especially on the eastern side of the Continental Divide, which has a higher elevation overall.<ref>{{Cite web |url=http://www.landscapephotoworld.com/glacier.html |title=Glacier National Park |date=October 25, 2015 |access-date=December 8, 2015 |last=Landscape Photo World |archive-date=April 10, 2017 |archive-url=https://web.archive.org/web/20170410051324/http://www.landscapephotoworld.com/glacier.html |url-status=live }}</ref> Snowfalls are significant over the course of the winter, with the largest accumulation occurring in the west. During the tourist season, daytime high temperatures average {{convert|60|to|70|F|C}}, and nighttime lows usually drop into the {{convert|40|F|C}} range. Temperatures in the high country may be much cooler. In the lower western valleys, daytime highs in the summer may reach {{convert|90|F|C|-1}}.<ref name="weather">{{cite web |title=Weather |publisher=National Park Service |url=https://www.nps.gov/glac/planyourvisit/weather.htm |date=December 21, 2006 |access-date=April 18, 2010 |archive-date=March 14, 2013 |archive-url=https://web.archive.org/web/20130314194632/http://www.nps.gov/glac/planyourvisit/weather.htm |url-status=live }}</ref>

Rapid temperature changes have been noted in the region. In [[Browning, Montana]], just east of the park in the Blackfeet Reservation, a world record temperature drop of {{convert|100|F-change}} in only 24 hours occurred on the night of January 23–24, 1916, when thermometers plunged from {{convert|44|to|-56|F|C}}.<ref name="record">{{cite web |title=Top Ten Montana Weather Events of the 20th Century |work=National Weather Service Unveils Montana's Top Ten Weather/Water/Climate Events of the 20th Century |publisher=National Weather Service |url=http://www.wrh.noaa.gov/tfx/tx.php?wfo=tfx&type=html&loc=text&fx=topweather |access-date=April 18, 2010 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154435/https://www.weather.gov/wrh/ErrorPage |url-status=live }}</ref>

Glacier National Park has a highly regarded global [[climate change]] research program. Based in West Glacier, with the main headquarters in [[Bozeman, Montana]], the [[U.S. Geological Survey]] has performed scientific research on specific climate change studies since 1992. In addition to the study of the retreating glaciers, research performed includes forest modeling studies in which fire ecology and habitat alterations are analyzed. Additionally, changes in alpine vegetation patterns are documented, watershed studies in which stream flow rates and temperatures are recorded frequently at fixed gauging stations, and atmospheric research in which [[UV-B]] radiation, ozone, and other atmospheric gases are analyzed over time. The research compiled contributes to a broader understanding of climate changes in the park. The data collected, when compared to other facilities scattered around the world, help to correlate these climatic changes on a global scale.<ref name="global">{{cite web |last=Fagre |first=Daniel |title=Global Change Research A Focus on Mountain Ecosystems |publisher=U.S. Geological Survey, Northern Rocky Mountain Science Center |date=April 13, 2010 |url=https://www.nrmsc.usgs.gov/research/global.htm |access-date=April 18, 2010 |archive-url=https://web.archive.org/web/20100528154749/http://www.nrmsc.usgs.gov/research/global.htm |archive-date=May 28, 2010}}</ref><ref name="wmi">{{cite web |title=Response of Western Mountain Ecosystems to Climatic Variability and Change: The Western Mountain Initiative |publisher=U.S. Geological Survey, Northern Rocky Mountain Science Center |date=February 11, 2009 |url=https://www.nrmsc.usgs.gov/files/norock/products/WMI_FactSheet_2008.pdf |access-date=January 12, 2014 |archive-url=https://web.archive.org/web/20130216123215/http://www.nrmsc.usgs.gov/files/norock/products/WMI_FactSheet_2008.pdf |archive-date=February 16, 2013}}</ref>

Glacier is considered to have excellent air and water quality. No major areas of dense human population exist anywhere near the region and industrial effects are minimized due to a scarcity of factories and other potential contributors of pollutants.<ref name="airquality">{{cite web |title=Air Quality |publisher=National Park Service |url=https://home.nps.gov/glac/learn/nature/airquality.htm |date=March 29, 2008 |access-date=April 18, 2010 |archive-date=November 6, 2012 |archive-url=https://web.archive.org/web/20121106124311/http://www.nps.gov/glac/naturescience/airquality.htm |url-status=live }}</ref> However, the sterile and cold lakes found throughout the park are easily contaminated by airborne pollutants that fall whenever it rains or snows, and some evidence of these pollutants has been found in park waters. Wildfires could also impact the quality of water. However, the pollution level is currently viewed as negligible, and the park lakes and waterways have a water quality rating of A-1, the highest rating given by the state of Montana.<ref name="waterquality">{{cite web |title=Water Quality |publisher=National Park Service |url=https://home.nps.gov/glac/learn/nature/waterquality.htm |date=March 27, 2008 |access-date=April 14, 2010 |archive-date=November 6, 2012 |archive-url=https://web.archive.org/web/20121106124358/http://www.nps.gov/glac/naturescience/waterquality.htm |url-status=live }}</ref>

{{Weather box|width=auto
|location = West Glacier, Montana (3148 ft), 1991&ndash;2020 normals, extremes 1948&ndash;present
|single line = Y
|collapsed = Y
|Jan avg record high F = 42.3
|Feb avg record high F = 44.9
|Mar avg record high F = 55.5
|Apr avg record high F = 69.4
|May avg record high F = 80.3
|Jun avg record high F = 85.7
|Jul avg record high F = 90.8
|Aug avg record high F = 90.8
|Sep avg record high F = 82.7
|Oct avg record high F = 69.3
|Nov avg record high F = 52.1
|Dec avg record high F = 41.7
|year avg record high F = 92.6

| Jan high F = 29.9
| Feb high F = 33.6
| Mar high F = 42.5
| Apr high F = 52.6
| May high F = 64.1
| Jun high F = 70.4
| Jul high F = 80.2
| Aug high F = 79.4
| Sep high F = 68.0
| Oct high F = 51.7
| Nov high F = 37.0
| Dec high F = 29.2
|year high F = 53.2
|Jan mean F = 24.6
|Feb mean F = 26.5
|Mar mean F = 33.8
|Apr mean F = 42.0
|May mean F = 51.6
|Jun mean F = 57.8
|Jul mean F = 64.9
|Aug mean F = 63.6
|Sep mean F = 54.4
|Oct mean F = 42.3
|Nov mean F = 31.7
|Dec mean F = 24.5
|year mean F = 43.1
| Jan low F = 19.3
| Feb low F = 19.4
| Mar low F = 25.1
| Apr low F = 31.4
| May low F = 39.0
| Jun low F = 45.1
| Jul low F = 49.6
| Aug low F = 47.9
| Sep low F = 40.8
| Oct low F = 32.9
| Nov low F = 26.4
| Dec low F = 19.9
|year low F = 33.1

|Jan avg record low F = -7.3
|Feb avg record low F = -3.1
|Mar avg record low F = 5.6
|Apr avg record low F = 19.9
|May avg record low F = 27.1
|Jun avg record low F = 34.6
|Jul avg record low F = 39.4
|Aug avg record low F = 36.9
|Sep avg record low F = 29.3
|Oct avg record low F = 17.4
|Nov avg record low F = 7.0
|Dec avg record low F = -1.6
|year avg record low F = -16.1

|Jan record high F = 55
|Feb record high F = 58
|Mar record high F = 66
|Apr record high F = 83
|May record high F = 90
|Jun record high F = 98
|Jul record high F = 99
|Aug record high F = 100
|Sep record high F = 95
|Oct record high F = 79
|Nov record high F = 65
|Dec record high F = 60
|year record high F =
|Jan record low F = -35
|Feb record low F = -32
|Mar record low F = -30
|Apr record low F = 3
|May record low F = 13
|Jun record low F = 24
|Jul record low F = 31
|Aug record low F = 26
|Sep record low F = 18
|Oct record low F = -3
|Nov record low F = -17
|Dec record low F = -36
|year record low F =
|precipitation colour = green
| Jan precipitation inch = 3.54
| Feb precipitation inch = 2.17
| Mar precipitation inch = 2.58
| Apr precipitation inch = 2.15
| May precipitation inch = 2.62
| Jun precipitation inch = 3.80
| Jul precipitation inch = 1.39
| Aug precipitation inch = 1.17
| Sep precipitation inch = 1.96
| Oct precipitation inch = 3.05
| Nov precipitation inch = 3.23
| Dec precipitation inch = 3.21
|year precipitation inch = 30.87
| unit precipitation days = 0.01 in
| Jan precipitation days = 17.9
| Feb precipitation days = 14.5
| Mar precipitation days = 15.0
| Apr precipitation days = 13.9
| May precipitation days = 13.6
| Jun precipitation days = 14.9
| Jul precipitation days = 8.5
| Aug precipitation days = 6.8
| Sep precipitation days = 9.6
| Oct precipitation days = 13.6
| Nov precipitation days = 16.3
| Dec precipitation days = 17.8
| year precipitation days = 162.4
|Jan snow inch = 32.0
|Feb snow inch = 16.0
|Mar snow inch = 14.0
|Apr snow inch = 3.1
|May snow inch = 0.5
|Jun snow inch = 0.0
|Jul snow inch = 0.0
|Aug snow inch = 0.0
|Sep snow inch = 0.0
|Oct snow inch = 2.0
|Nov snow inch = 16.2
|Dec snow inch = 31.4
|year snow inch = 115.2
|unit snow days = 0.1 in
|Jan snow days = 13.9
|Feb snow days = 10.5
|Mar snow days = 6.2
|Apr snow days = 1.8
|May snow days = 0.3
|Jun snow days = 0.0
|Jul snow days = 0.0
|Aug snow days = 0.0
|Sep snow days = 0.0
|Oct snow days = 1.0
|Nov snow days = 6.7
|Dec snow days = 14.2
|year snow days = 54.6
|source 1 = NOAA<ref>{{cite web |url=https://w2.weather.gov/climate/xmacis.php?wfo=mso |title=NOWData - NOAA Online Weather Data |publisher=[[National Oceanic and Atmospheric Administration]] |access-date=June 9, 2021 |archive-date=August 3, 2021 |archive-url=https://web.archive.org/web/20210803052627/https://w2.weather.gov/climate/xmacis.php?wfo=mso |url-status=live }}</ref><ref>{{cite web |url=https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&startDate=0001-01-01&endDate=9996-12-31&stations=USC00248809&format=pdf |title=Summary of Monthly Normals 1991-2020 |publisher=[[National Oceanic and Atmospheric Administration]] |access-date=June 9, 2021 |archive-date=August 2, 2021 |archive-url=https://web.archive.org/web/20210802224358/https://www.ncei.noaa.gov/access/services/data/v1?dataset=normals-monthly-1991-2020&startDate=0001-01-01&endDate=9996-12-31&stations=USC00248809&format=pdf |url-status=live }}</ref> }}

==Wildlife and ecology==
{{See also|Ecology of the Rocky Mountains}}

===Flora===
[[File:Xerophyllum tenax - Glacier National Park.jpg|thumb|upright|[[Xerophyllum tenax|Beargrass]] is a tall flowering plant commonly found throughout the park.]]
Glacier is part of a large preserved [[ecosystem]] collectively known as the "Crown of the Continent Ecosystem", all of which is a primarily untouched wilderness of a pristine quality. Virtually all the plants and animals which existed at the time European explorers first entered the region are present in the park today.<ref name="bio">{{cite web |title=The Crown of the Continent Ecosystem |work=Biodiversity |publisher=National Park Service |url=http://www.nps.gov/archive/glac/resources/bio1.htm#Crown |access-date=April 18, 2010 |archive-date=March 13, 2013 |archive-url=https://web.archive.org/web/20130313135833/http://www.nps.gov/blank.png#Crown }}</ref>

A total of over 1,132 plant species have been identified parkwide.<ref name="flora">{{cite web |title=Plants |work=Nature and Science |publisher=National Park Service |url=https://home.nps.gov/glac/learn/nature/plants.htm |date=March 5, 2008 |access-date=April 18, 2010 |archive-date=January 29, 2013 |archive-url=https://web.archive.org/web/20130129073258/http://www.nps.gov/glac/naturescience/plants.htm |url-status=live }}</ref> The predominantly [[coniferous]] forest is home to various species of trees such as the [[Engelmann spruce]], [[Douglas fir]], [[subalpine fir]], [[limber pine]] and [[western larch]], which is a [[deciduous]] conifer, producing cones but losing its needles each fall. [[Populus sect. Aegiros|Cottonwood]] and [[aspen]] are the more common deciduous trees and are found at lower elevations, usually along lakes and streams.<ref name="montane"/> The [[tree line|timberline]] on the eastern side of the park is almost {{convert|800|ft|m|0}} lower than on the western side of the Continental Divide, due to exposure to the colder winds and weather of the Great Plains. West of the Continental Divide, the forest receives more moisture and is more protected from the winter, resulting in a more densely populated forest with taller trees. Above the forested valleys and mountain slopes, [[alpine tundra]] conditions prevail, with grasses and small plants eking out an existence in a region that enjoys as little as three months without snow cover.<ref name="wildflowers">{{cite web |title=Wildflowers |work=Nature and Science |publisher=National Park Service |url=https://home.nps.gov/glac/learn/nature/wildflowers.htm |date=March 25, 2008 |access-date=April 18, 2010 |archive-date=December 21, 2012 |archive-url=https://web.archive.org/web/20121221103855/http://www.nps.gov/glac/naturescience/wildflowers.htm |url-status=live }}</ref> Thirty species of plants are found only in the park and surrounding national forests.<ref name="flora"/> [[Beargrass]], a tall flowering plant, is commonly found near moisture sources, and is relatively widespread during July and August. Wildflowers such as [[Mimulus|monkeyflower]], [[Erythronium grandiflorum|glacier lily]], [[fireweed]], [[Balsamorhiza|balsamroot]] and [[Castilleja|Indian paintbrush]] are also common.<ref name="101 Wildflowers">{{cite web |url=http://npshistory.com/handbooks/cooperating_associations/glac/gnha-5-c1951.pdf |title=101 Wildflowers of Glacier National Park |last=Sharpe |first=Grant |publisher=Glacier National History Association |access-date=January 2, 2021 |archive-date=January 30, 2022 |archive-url=https://web.archive.org/web/20220130153609/http://www.npshistory.com/handbooks/cooperating_associations/glac/gnha-5-c1951.pdf |url-status=live }}</ref><ref name="Glacier National Park 2019">{{cite web |title=Common alpine wildflowers |website=Glacier National Park |date=June 12, 2019 |url=https://www.pc.gc.ca/en/pn-np/bc/glacier/nature/faune-flore-fauna-flora/fleurs-flowers |access-date=January 2, 2021 |archive-date=December 13, 2022 |archive-url=https://web.archive.org/web/20221213154946/https://parks.canada.ca/pn-np/bc/glacier/nature/faune-flore-fauna-flora/fleurs-flowers |url-status=live }}</ref>

The forested sections fall into three major climatic zones. The west and northwest are dominated by spruce and fir and the southwest by [[Thuja plicata|red cedar]] and [[Tsuga|hemlock]]; the areas east of the Continental Divide are a combination of mixed pine, spruce, fir and prairie zones. The cedar-hemlock groves along the [[Lake McDonald]] valley are the easternmost examples of this Pacific climatic ecosystem.<ref name="forest">{{cite web |title=Forests |work=Nature and Science |publisher=National Park Service |url=https://www.nps.gov/glac/naturescience/forests.htm |date=March 29, 2008 |access-date=April 18, 2010 |archive-date=March 7, 2013 |archive-url=https://web.archive.org/web/20130307041549/http://www.nps.gov/glac/naturescience/forests.htm |url-status=live }}</ref>

[[Whitebark pine]] communities have been heavily damaged due to the effects of [[Cronartium ribicola|blister rust]], a non native fungus. In Glacier and the surrounding region, 30% of the whitebark pine trees have died and over 70% of the remaining trees are currently infected. The whitebark pine provides a high fat pine cone seed, commonly known as the pine nut, that is a favorite food of [[red squirrel]]s and [[Clark's nutcracker]]. Both [[grizzly bear|grizzlies]] and [[American black bear|black bears]] are known to raid squirrel caches of pine nuts, one of the bears' favorite foods. Between 1930 and 1970, efforts to control the spread of blister rust were unsuccessful, and continued destruction of whitebark pines appears likely, with attendant negative impacts on dependent species.<ref name="whitebark">{{cite web |title=Whitebark Pine Communities |publisher=Northern Rocky Mountain Science Center, U.S. Geological Survey |date=April 13, 2010 |url=https://www.nrmsc.usgs.gov/research/whitebar.htm |access-date=April 18, 2010 |archive-url=https://web.archive.org/web/20100527120712/http://www.nrmsc.usgs.gov/research/whitebar.htm |archive-date=May 27, 2010}}</ref>

===Fauna===
{{See also|List of birds of Glacier National Park (U.S.)|Mammals of Glacier National Park (U.S.)}}
[[File:A Berry Hillside (51860257214).jpg|alt=a bear on a hillside with green vegetation|thumb|Over 1,000 [[grizzly bear]]s live in the region {{as of|2021|lc=y}}.<ref name="NY Times-2021" />]]
Virtually all the historically known plant and animal species, with the exception of the [[Plains bison|bison]] and woodland [[caribou]], are still present, providing biologists with an intact ecosystem for plant and animal research. Two [[threatened species]] of mammals, the grizzly bear and the [[Canada lynx|lynx]],{{refn|name=n1|group=note|The grizzly bear and Canadian lynx are listed as threatened species only in the [[contiguous United States]].<ref>[https://www.nps.gov/glac/learn/nature/bears.htm "Glacier National Park – Bears"] {{Webarchive|url=https://web.archive.org/web/20191211112502/https://www.nps.gov/glac/learn/nature/bears.htm |date=December 11, 2019 }}. ''nps.gov''. National Park Service. November 6, 2017. Retrieved November 25, 2018.</ref><ref name="mammals"/> The [[International Union for Conservation of Nature|IUCN]] lists them both as "least concern" (LC) generally.<ref>{{cite iucn |author=McLellan, B.N. |author2=Proctor, M.F. |author3=Huber, D. |author4=Michel, S. |date=2017 |title=''Ursus arctos'' |volume=2017 |article-number=e.T41688A121229971 |doi=10.2305/IUCN.UK.2017-3.RLTS.T41688A121229971.en |access-date=11 November 2021}}</ref><ref>{{cite iucn |author=Vashon, J. |date=2016 |title=''Lynx canadensis'' |volume=2016 |article-number=e.T12518A101138963 |doi=10.2305/IUCN.UK.2016-2.RLTS.T12518A101138963.en |access-date=11 November 2021}}</ref>}} are found in the park.<ref name="mammals"/> Although their numbers remain at historical levels, both are listed as threatened because in nearly every other region of the U.S. outside of [[Alaska]], they are either extremely rare or absent from their historical range. On average, one or two bear attacks on humans occur each year.<ref name="bear">{{cite web |title=If you encounter a bear |work=Bears |publisher=National Park Service |url=http://www.nps.gov/archive/glac/resources/bears2.htm#Pepper |archive-url=https://web.archive.org/web/20061222220732/http://www.nps.gov/archive/glac/resources/bears2.htm |archive-date=December 22, 2006 |access-date=April 18, 2010}}</ref> There have been 11 bear-related deaths since 1971, and 20 non-fatal injuries since 2001.<ref name="Hanson Brown Press 2021">{{cite web |last1=Hanson |first1=Amy Beth |last2=Brown |first2=Matthew |last3=Press |first3=Associated |title=Grizzly kills woman on cycling trip in Montana after pulling her from tent |website=Anchorage Daily News |date=2021-07-08 |url=https://www.adn.com/nation-world/2021/07/08/grizzly-bear-kills-bicyclist-after-pulling-her-from-tent-in-montana/ |access-date=2022-02-06 |archive-date=June 23, 2022 |archive-url=https://web.archive.org/web/20220623075723/https://www.adn.com/nation-world/2021/07/08/grizzly-bear-kills-bicyclist-after-pulling-her-from-tent-in-montana/ |url-status=live }}</ref> The exact number of grizzlies and lynx in the park is unknown;<ref name="mammals"/><ref name="lynx">{{cite web |last=Hudson |first=Laura |title=Lynx inventories under way in the Intermountain Region |publisher=National Park Service |url=http://www2.nature.nps.gov/yearinreview/yir2001/02_management/02_1_hudson.html |date=January 10, 2008 |access-date=April 18, 2010 |archive-url=https://web.archive.org/web/20090508081805/http://www.nature.nps.gov/YearinReview/yir2001/02_management/02_1_hudson.html |archive-date=May 8, 2009}}</ref> however, the first ever scientific survey of the lynx population in the park was completed in 2021. The collected data will help researchers determine the number of individual lynx that populate certain areas of the park.<ref name="Weber 2021">{{cite web |last=Weber |first=Jeremy |title=Recent study aims to estimate lynx population in Glacier Park |website=Daily Inter Lake |date=2021-12-05 |url=https://dailyinterlake.com/news/2021/dec/05/recent-study-aims-estimate-lynx-population-glacier/ |access-date=2022-02-06 |archive-date=February 6, 2022 |archive-url=https://web.archive.org/web/20220206220541/https://dailyinterlake.com/news/2021/dec/05/recent-study-aims-estimate-lynx-population-glacier/ |url-status=live }}</ref> Reports from state and federal resource agencies, such as the [[Montana Department of Fish, Wildlife and Parks]], indicate that as of 2021, the grizzly population throughout the millions of acres in and around Glacier Park has climbed to around 1,051–more than triple the 300 or so population estimates in 1975 when grizzlies were first listed as a threatened species.<ref name="NY Times-2021">{{cite web |title=Grizzly Bear Death Rates Are Climbing |website=The New York Times |date=2021-10-07 |url=https://www.nytimes.com/2020/02/10/science/grizzly-bears-deaths.html |access-date=2022-02-06 |archive-date=November 25, 2022 |archive-url=https://web.archive.org/web/20221125132801/https://www.nytimes.com/2020/02/10/science/grizzly-bears-deaths.html |url-status=live }}</ref><ref>{{cite web |title=Montana seeks to end protections for Glacier-area grizzlies |website=Montana Public Radio |date=2021-12-07 |url=https://www.mtpr.org/montana-news/2021-12-06/montana-seeks-to-end-protections-for-glacier-area-grizzlies |access-date=2022-02-06 |archive-date=March 30, 2022 |archive-url=https://web.archive.org/web/20220330022355/https://www.mtpr.org/montana-news/2021-12-06/montana-seeks-to-end-protections-for-glacier-area-grizzlies |url-status=live }}</ref> While exact population numbers for grizzlies and the smaller [[American black bear|black bear]] are still unknown, biologists have implemented a variety of methods in their efforts to achieve more accuracy in determining population range.<ref name="dan">{{cite web |last=Kendall |first=Katherine |author2=Lisette Waits |title=Greater Glacier Bear DNA Project 1997–2002 |work=Northern Divide Grizzly Bear Project |publisher=United States Geological Survey |url=https://www.nrmsc.usgs.gov/research/glac_beardna.htm |date=April 13, 2010 |access-date=April 18, 2010 |archive-url=https://web.archive.org/web/20100421135534/http://www.nrmsc.usgs.gov/research/glac_beardna.htm |archive-date=April 21, 2010}}</ref> Another study has indicated that the [[wolverine]], another very rare mammal in the lower 48 states, also lives in the park.<ref name="wolverine">{{cite web |last=Copeland |first=Jeff |author2=Rick Yates |author3=Len Ruggiero |title=Wolverine Population Assessment in Glacier National Park, Montana |publisher=Wolverine Foundation |date=June 16, 2003 |url=http://wolverinefoundation.org/wp-content/uploads/2011/02/gnpprog_sprng03.pdf |access-date=April 18, 2010 |archive-date=March 17, 2012 |archive-url=https://web.archive.org/web/20120317173641/http://wolverinefoundation.org/wp-content/uploads/2011/02/gnpprog_sprng03.pdf |url-status=live }}</ref> There were only three or four [[wolf]] packs remaining in the park when it was established. Early rangers used guns, traps, and poison to successfully eliminate the species from the park by 1936.<ref>{{NPS |author=Jaclyn |date=October 24, 2017 |title=Of Wolves and Wilderness - Glacier National Park |url=https://www.nps.gov/glac/blogs/of-wolves-and-wilderness.htm |access-date=2023-10-07 |publisher=U.S. National Park Service |language=en}}</ref> Wolves recolonized Glacier National Park naturally during the 1980s.<ref name="wolf">{{cite web |title=Gray Wolf&nbsp;– Canis lupus |work=Montana Field Guide |publisher=State of Montana |url=http://fieldguide.mt.gov/detail_AMAJA01030.aspx |access-date=April 18, 2010 |archive-date=May 8, 2013 |archive-url=https://web.archive.org/web/20130508081524/http://fieldguide.mt.gov/detail_AMAJA01030.aspx |url-status=live }}</ref> Sixty-two species of mammals have been documented including [[American badger|badger]], [[North American river otter|river otter]], [[North American porcupine|porcupine]], [[American mink|mink]], [[American marten|marten]], [[fisher (animal)|fisher]], two species of [[marmot]]s, six species of [[bat]]s, and numerous other small mammals.<ref name="check"/> Other mammals such as the [[mountain goat]] (the official park symbol), [[bighorn sheep]], [[moose]], [[Rocky Mountain elk|elk]], [[mule deer]], [[striped skunk|skunk]], [[white-tailed deer]], [[bobcat]], [[coyote]], and [[North American cougar|cougar]] are either plentiful or common.<ref name="check">{{cite web |title=Mammal Checklist |work=Mammals of Glacier National Park Field Checklist |publisher=National Park Service |url=http://www.nps.gov/glac/naturescience/mammalchecklist.htm |date=December 21, 2006 |access-date=April 18, 2010 |archive-url=https://web.archive.org/web/20100510001220/http://www.nps.gov/glac/naturescience/mammalchecklist.htm |archive-date=May 10, 2010 }}</ref>

[[File:2015-06-19 Glacier National Park (U.S.) 8625.jpg|thumb|left|A [[marmot]] above [[Hidden Lake (Flathead County, Montana)|Hidden Lake]]]]
Over 260 species of birds have been recorded, with raptors such as the [[bald eagle]], [[golden eagle]], [[peregrine falcon]], [[osprey]] and several species of [[hawk]]s residing year round.<ref name="birds">{{cite web |date=December 5, 2019 |title=Birds |url=https://www.nps.gov/glac/learn/nature/birds.htm |access-date=5 May 2022 |work=Nature and Science |publisher=National Park Service |archive-date=October 27, 2022 |archive-url=https://web.archive.org/web/20221027124650/https://www.nps.gov/glac/learn/nature/birds.htm |url-status=live }}</ref> The [[harlequin duck]] is a colorful species of waterfowl found in the lakes and waterways. The [[great blue heron]], [[Bewick's swan|tundra swan]], [[Canada goose]] and [[American wigeon]] are species of waterfowl more commonly encountered in the park. [[Great horned owl]], [[Clark's nutcracker]], [[Steller's jay]], [[pileated woodpecker]] and [[cedar waxwing]] reside in the dense forests along the mountainsides, and in the higher altitudes, the [[White-tailed ptarmigan|ptarmigan]], [[American sparrow|timberline sparrow]] and [[Mountain finch|rosy finch]] are the most likely to be seen.<ref name="birds"/><ref name="birds2">{{cite web |title=Birds of Glacier National Park Field Checklist |publisher=National Park Service |url=http://www.nps.gov/archive/glac/pdf/birds2005.pdf |archive-url=https://web.archive.org/web/20061229224311/http://www.nps.gov/archive/glac/pdf/birds2005.pdf |archive-date=December 29, 2006 |year=2005 |access-date=April 18, 2010}}</ref> The Clark's nutcracker is less plentiful than in past years due to the decline in the number of [[whitebark pine]]s.<ref name="whitebark"/>

Because of the colder climate, [[ectothermic]] reptiles are all but absent, with two species of [[garter snake]] and the [[Painted turtle|western painted turtle]] being the only three reptile species proven to exist.<ref name="reptiles">{{cite web |title=Reptiles |work=Nature and Science |publisher=National Park Service |url=https://home.nps.gov/glac/learn/nature/reptiles.htm |date=March 5, 2008 |access-date=April 18, 2010 |archive-date=March 8, 2013 |archive-url=https://web.archive.org/web/20130308090807/http://www.nps.gov/glac/naturescience/reptiles.htm |url-status=live }}</ref> Similarly, only six species of [[amphibian]]s are documented, although those species exist in large numbers. After a forest fire in 2001, a few park roads were temporarily closed the following year to allow thousands of [[western toad]]s to migrate to other areas.<ref name="toad">{{cite web |title=Amphibians |work=Nature and Science |publisher=National Park Service |url=https://www.nps.gov/glac/learn/nature/amphibians.htm |access-date=April 18, 2010 |archive-date=November 7, 2012 |archive-url=https://web.archive.org/web/20121107114844/http://www.nps.gov/glac/naturescience/amphibians.htm |url-status=live }}</ref>

[[File:Pronghorn Clubtail Dragonfly.jpg|thumb|A Pronghorn Clubtail [[Dragonfly]] at Lake McDonald]] 
A total of 23 species of fish reside in park waters, and native game fish species found in the lakes and streams include the [[westslope cutthroat trout]], [[northern pike]], [[Coregonus|mountain whitefish]], [[Sockeye salmon|kokanee salmon]] and [[Arctic grayling]]. Glacier is also home to the threatened [[bull trout]], which is illegal to possess and must be returned to the water if caught inadvertently.<ref name="bull trout">{{cite web |title=Preserving Glacier's Native Bull Trout |publisher=National Park Service |url=http://www.glaciermt.com/pdf/bulltrout.pdf |access-date=April 18, 2010 |archive-url=https://web.archive.org/web/20110711100603/http://www.glaciermt.com/pdf/bulltrout.pdf |archive-date=July 11, 2011}}</ref> Introduction in previous decades of [[lake trout]] and other non-native fish species has greatly impacted some native fish populations, especially the bull trout and west slope cutthroat trout.<ref name="fish">{{cite web |title=Fish |work=Nature and Science |publisher=National Park Service |url=https://www.nps.gov/glac/learn/nature/fish.htm |date=March 5, 2008 |access-date=April 18, 2010 |archive-date=November 6, 2012 |archive-url=https://web.archive.org/web/20121106124623/http://www.nps.gov/glac/naturescience/fish.htm |url-status=live }}</ref>

===Fire ecology===
[[File:GNP Wildfires 2003.jpg|thumb|Wildfires burned 13% of the park in 2003.]]
[[Wildfire|Forest fire]]s were viewed for many decades as a threat to protected areas such as forests and parks. As a better understanding of [[fire ecology]] developed after the 1960s, forest fires were understood to be a natural part of the ecosystem. The earlier policies of suppression resulted in the accumulation of dead and decaying trees and plants, which would normally have been reduced had fires been allowed to burn. Many species of plants and animals actually need wildfires to help replenish the soil with nutrients and to open up areas that allow grasses and smaller plants to thrive.<ref name="fire2">{{cite web |title=A Fire Ecosystem |work=Glacier National Park Wildland Fire Management |publisher=National Park Service |url=http://www.nps.gov/archive/glac/resources/fire_2.htm |archive-url=https://web.archive.org/web/20061229021527/http://www.nps.gov/archive/glac/resources/fire_2.htm |archive-date=December 29, 2006 |access-date=April 18, 2010}}</ref>
Glacier National Park has a fire management plan which ensures that human-caused fires are generally suppressed. In the case of natural fires, the fire is monitored and suppression is dependent on the size and threat the fire may pose to human safety and structures.<ref name="fire3">{{cite web |title=Working With Fire: a look at Fire Management |work=Glacier National Park Wildland Fire Management |publisher=National Park Service |url=http://www.nps.gov/archive/glac/resources/fire_3.htm |archive-url=https://web.archive.org/web/20061230052749/http://www.nps.gov/archive/glac/resources/fire_3.htm |archive-date=December 30, 2006 |access-date=April 18, 2010}}</ref>

Increased population and the growth of suburban areas near parklands, has led to the development of what is known as Wildland Urban Interface Fire Management, in which the park cooperates with adjacent property owners in improving safety and fire awareness. This approach is common to many other protected areas. As part of this program, houses and structures near the park are designed to be more fire resistant. Dead and fallen trees are removed from near places of human habitation, reducing the available fuel load and the risk of a catastrophic fire, and advance warning systems are developed to help alert property owners and visitors about forest fire potentials during a given period of the year.<ref name="urban">{{cite web |title=Wildland Urban Interface |work=Glacier National Park Wildland Fire Management |publisher=National Park Service |url=http://www.nps.gov/archive/glac/resources/fire_4.htm |archive-url=https://web.archive.org/web/20061212051929/http://www.nps.gov/archive/glac/resources/fire_4.htm |archive-date=December 12, 2006 |access-date=April 18, 2010}}</ref> Glacier National Park has an average of 14 fires with {{cvt|5000|acre|km2}} burnt each year.<ref name="fire4">{{cite web |title=Fire in Glacier National Park |work=Glacier National Park Wildland Fire Management |publisher=National Park Service |url=http://www.nps.gov/archive/glac/resources/fires.htm |archive-url=https://web.archive.org/web/20061205053836/http://www.nps.gov/archive/glac/resources/fires.htm |archive-date=December 5, 2006 |access-date=April 18, 2010}}</ref> In 2003, {{cvt|136000|acre|km2}} burned in the park after a five-year drought and a summer season of almost no precipitation. This was the most area transformed by fire since the creation of the park in 1910.<ref name="fire">{{cite web |title=Fire Regime |publisher=National Park Service, U.S. Department of the Interior |url=http://www.nps.gov/glac/naturescience/fireregime.htm |date=March 29, 2008 |access-date=April 13, 2010 |archive-date=November 6, 2012 |archive-url=https://web.archive.org/web/20121106124127/http://www.nps.gov/glac/naturescience/fireregime.htm }}</ref>

==Recreation==
[[File:Jammer.jpg|thumb|left|Glacier National Park Red Jammer bus]]
Glacier is distant from major cities. The closest airport is in [[Kalispell, Montana]], southwest of the park. Amtrak's [[Empire Builder]] stops seasonally at [[East Glacier Park station|East Glacier]], and year-round at [[West Glacier station|West Glacier]] and [[Essex, Montana|Essex]]. A fleet of restored 1930s [[White Motor Company]] coaches, called [[Red Jammers]], offer tours on all the main roads in the park. The drivers of the buses are called "Jammers", due to the gear-jamming that formerly occurred during the vehicles' operation. The tour buses were rebuilt in 2001 by Ford Motor Company. The bodies were removed from their original chassis and built on modern Ford E-Series van chassis.<ref>{{Cite web |url=http://www.seriouswheels.com/cars/top-1930s-White-Glacier-National-Park-Red-Bus.htm |title=1930s White Glacier National Park Red Bus |website=www.seriouswheels.com |access-date=January 6, 2011 |archive-date=July 15, 2019 |archive-url=https://web.archive.org/web/20190715140633/http://www.seriouswheels.com/cars/top-1930s-White-Glacier-National-Park-Red-Bus.htm |url-status=live }}</ref> They were also converted to run on [[propane]] to lessen their environmental impact.<ref name="reds">{{cite web |author=Vanderbilt, Amy M |year=2002 |title=On the Road Again: Glacier National Park's Red Buses |publisher=National Park Service |url=http://crm.cr.nps.gov/archive/25-05/25-05-06.pdf |access-date=April 18, 2010 |archive-url=https://web.archive.org/web/20100527122516/http://crm.cr.nps.gov/archive/25-05/25-05-06.pdf |archive-date=May 27, 2010}}</ref> Later, new hybrid engines were adopted.<ref>{{cite news |author=Chaney, Rob |date=December 5, 2018 |title=Glacier National Park 'jammer buses' go quiet with new hybrid engines |newspaper=The Missoulian |url=https://missoulian.com/lifestyles/recreation/glacier-national-park-jammer-buses-go-quiet-with-new-hybrid/article_56c794f1-7dc0-5970-b8a1-64af5f96d60e.html |access-date=21 January 2020 |archive-date=January 24, 2022 |archive-url=https://web.archive.org/web/20220124115427/https://missoulian.com/lifestyles/recreation/glacier-national-park-jammer-buses-go-quiet-with-new-hybrid/article_56c794f1-7dc0-5970-b8a1-64af5f96d60e.html |url-status=live }}</ref> {{As of|2017}}, 33 of original 35 are still in operation.<ref>{{cite news |url=https://www.greatfallstribune.com/story/outdoors/2017/06/05/jamming-historic-red-buses/314696001/ |title=Jamming with the historic red buses |author=Dettmer, Sarah |date=June 5, 2017 |newspaper=Great Falls Tribune |access-date=23 January 2020 |archive-date=July 3, 2022 |archive-url=https://web.archive.org/web/20220703171437/https://www.greatfallstribune.com/story/outdoors/2017/06/05/jamming-historic-red-buses/314696001/ |url-status=live }}</ref>

Historic wooden tour boats, some dating back to the 1920s, operate on some of the larger lakes. Several of these boats have been in continuous seasonal operation at Glacier National Park since 1927 and carry up to 80 passengers. Three of these decades-old boats were added to the National Register of Historic Places in January 2018.<ref>{{cite web |last1=Franz |first1=Justin |title=Glacier National Park Boats Added to Historic Register |url=http://flatheadbeacon.com/2018/01/02/glacier-national-park-boats-added-historic-register/ |website=FlatheadBeacon.com |access-date=January 2, 2018 |date=January 2, 2018 |archive-date=January 2, 2018 |archive-url=https://web.archive.org/web/20180102161849/http://flatheadbeacon.com/2018/01/02/glacier-national-park-boats-added-historic-register/ |url-status=live }}</ref>
{{Multiple image|total_width=280|align=right|direction=vertical 
|image1= Highline Trail (4169004303).jpg |caption1= Hikers on the [[Garden Wall]] section of the [[Highline Trail (Glacier National Park)|Highline Trail]], north of the [[Logan Pass]] visitor center, with Going-to-the-Sun Road below 
|image2=Dragons Tail.jpg|caption2=Climbers descend from the ridge of Dragon's Tail near [[Logan Pass]]
}}

Hiking is popular in the park. Over half of the visitors to the park report taking a hike on the park's nearly {{cvt|700|mi|km|0}} of trails.<ref name="trails">{{cite web |author=Hayden, Bill |date=October 1, 2008 |title=Hiking the Trails |publisher=National Park Service |url=https://www.nps.gov/glac/planyourvisit/hikingthetrails.htm |access-date=April 18, 2010 |archive-date=March 28, 2013 |archive-url=https://web.archive.org/web/20130328091617/http://www.nps.gov/glac/planyourvisit/hikingthetrails.htm |url-status=live }}</ref> {{cvt|110|mi|km|0}} of the [[Continental Divide National Scenic Trail]] spans most of the distance of the park north to south, with a few alternative routes at lower elevations if high altitude [[mountain pass|passes]] are closed due to snow. The [[Pacific Northwest National Scenic Trail]] crosses the park on {{cvt|52|mi|km|0}} from east to west.<ref>{{cite web |title=About the Trail |website=Pacific Northwest National Scenic Trail |url=https://www.fs.usda.gov/main/pnt/about |access-date=January 2, 2021 |archive-date=March 20, 2021 |archive-url=https://web.archive.org/web/20210320055318/https://www.fs.usda.gov/main/pnt/about |url-status=live }}</ref>

Many day hikes can be taken in the park. Back-country camping is allowed at campsites along the trails. A permit is required and can be obtained from certain visitor centers or arranged for in advance. Much of Glacier's backcountry is usually inaccessible to hikers until early June due to accumulated snowpack and avalanche risk, and many trails at higher altitudes remain snow-packed until July.<ref name="winterhike">Archived at [https://ghostarchive.org/varchive/youtube/20211211/aLd2MT5TKXs Ghostarchive]{{cbignore}} and the [https://web.archive.org/web/20130729064746/http://www.youtube.com/watch?v=aLd2MT5TKXs Wayback Machine]{{cbignore}}: {{cite web |title=Winter Hiking in Glacier National Park, Montana |date=May 20, 2011 |publisher=Youtube |url=https://www.youtube.com/watch?v=aLd2MT5TKXs |access-date=July 8, 2011}}{{cbignore}}</ref> Campgrounds that allow vehicle access are found throughout the park, most of which are near one of the larger lakes. The campgrounds at [[St. Mary, Montana|St. Mary]] and at Apgar are open year-round, but conditions are primitive in the off-season, as the restroom facilities are closed and there is no running water. All campgrounds with vehicle access are usually open from mid-June until mid-September.<ref name="backcountry">{{cite web |title=Backcountry Guide 2006 |publisher=National Park Service |url=http://www.nps.gov/archive/glac/pdf/BCGuide-web.pdf |archive-url=https://web.archive.org/web/20061230223619/http://www.nps.gov/archive/glac/pdf/BCGuide-web.pdf |archive-date=December 30, 2006 |access-date=April 18, 2010}}</ref> Guide and shuttle services are also available.<ref name="GNP 2020">{{cite web |title=Getting Around |website=Glacier National Park (U.S. National Park Service) |date=January 16, 2020 |url=https://www.nps.gov/glac/planyourvisit/gettingaround.htm |access-date=January 2, 2021 |archive-date=September 27, 2022 |archive-url=https://web.archive.org/web/20220927211309/https://www.nps.gov/glac/planyourvisit/gettingaround.htm |url-status=live }}</ref>

The park attracts many mountain climbers, with many routes having rapid elevation gains. The mountains' sedimentary rocks fracture easily.<ref>{{Cite book |last=Edwards |first=J. Gordon |url=https://books.google.com/books?id=vvUWEQAAQBAJ&pg=PA7 |title=Climber's Guide to Glacier National Park |date=2023-12-19 |publisher=Rowman & Littlefield |isbn=978-1-4930-8206-3 |language=en}}</ref> The Glacier Mountaineering Society sponsors climbing in the park and catalogues its peaks.<ref>{{Cite web |last=Scott |first=Tristan |date=2023-11-27 |title=The New Guard of Glacier Mountaineering |url=https://flatheadbeacon.com/2023/11/27/the-new-guard-of-glacier-mountaineering/ |access-date=2025-05-19 |website=Flathead Beacon |language=en}}</ref>

The park is a popular destination for kayaking and [[fly fishing]].<ref>{{cite book |last1=Schneider |first1=Russ |title=Fishing Glacier National Park: An Angler's Authoritative Guide to More Than 250 Streams, Rivers, and Mountain Lakes |date=2021 |publisher=[[Lyons Press]] |location=Guilford, Connecticut |isbn=978-1-4930-4549-5 |pages=1–3 |edition=3rd}}</ref> A permit is not required to fish in park waters. The threatened bull trout must be released immediately back to the water if caught; otherwise, the regulations on limits of catch per day are liberal.<ref name="fishregs">{{cite web |title=Fishing Regulations 2008–2009 |publisher=National Park Service |url=http://www.nps.gov/glac/planyourvisit/upload/08Fishing.pdf |access-date=April 18, 2010 |archive-date=November 6, 2012 |archive-url=https://web.archive.org/web/20121106132229/http://www.nps.gov/glac/planyourvisit/upload/08Fishing.pdf }}</ref><ref name="Glacier National Park-2018" />

Winter recreation in Glacier is limited. [[Snowmobile|Snowmobiling]] is illegal throughout the park. [[Cross-country skiing]] is permitted in the lower altitude valleys away from avalanche zones.<ref name="winter">{{cite web |title=Operating Hours & Seasons |publisher=National Park Service |url=https://www.nps.gov/glac/planyourvisit/hours.htm |date=January 5, 2010 |access-date=April 18, 2010 |archive-date=March 13, 2013 |archive-url=https://web.archive.org/web/20130313074800/http://www.nps.gov/glac/planyourvisit/hours.htm |url-status=live }}</ref>

== See also ==
{{portal|Montana}}
*[[Outline of Glacier National Park (U.S.)|Outline of Glacier National Park]]
*[[List of national parks of the United States]]
*[[Mount James]]

== Notes ==

{{Reflist|group=note}}

==References==
{{Reflist|30em}}

==Further reading==
*{{cite web |author=National Park Service |title=Glacier National Park |url=https://www.nps.gov/glac/index.htm}}
*{{cite web |author=Parks Canada |title=Waterton Lakes National Park of Canada |url=http://www.pc.gc.ca/eng/pn-np/ab/waterton/index.aspx |date=March 28, 2017}}
*{{cite web |author=Sierra Club |title=Glacier National Park is a Global Warming Laboratory |work=Global Warming and Energy |url=http://www.sierraclub.org/globalwarming/articles/glacier.asp |archive-url=https://web.archive.org/web/20040812141646/http://www.sierraclub.org/globalwarming/articles/glacier.asp |archive-date=August 12, 2004}}
*{{cite web |author=U.S. Geological Survey |title=Glacier retreat in Glacier National Park, Montana |work=Northern Rocky Mountain Science Center research |url=https://www.nrmsc.usgs.gov/research/glacier_retreat.htm}}
*{{cite web |author=U.S. Geological Survey |title=Modeled Climate-Induced Glacier Change in Glacier National Park, 1850–2100 |url=https://www.nrmsc.usgs.gov/research/glacier_model.htm |archive-url=https://web.archive.org/web/20100527140530/http://www.nrmsc.usgs.gov/research/glacier_model.htm |archive-date=May 27, 2010}}
*{{cite web |author=U.S. Geological Survey |title=USGS Repeat Photography Project, Glacier National Park, MT |url=https://nrmsc.usgs.gov/repeatphoto/overview.htm}}
*[https://web.archive.org/web/20101128035128/http://rchs.com/dutiful_son%20Louis%20Hill.htm Dutiful Son: Louis W. Hill Sr. Book], Book about Louis W. Hill Sr., son and successor of empire builder James J. Hill and major force behind the establishment and development of Glacier National Park.
*Bottomly-O'looney, Jennifer, and Deirdre Shaw. "Glacier National Park: People, a Playground, and a Park". ''Montana: The Magazine of Western History'' 60#1 (2010): 42–55.
*Harper, Andrew C. "Conceiving Nature: The Creation of Montana's Glacier National Park". ''Montana: The Magazine of Western History'' 60#1 (2010): 3–24.
*{{cite book |author=[[Mary Roberts Rinehart|Roberts Rinehart, Mary]] |title=Through Glacier Park: Seeing America First with Howard Eaton |date=May 1916 |url=https://www.gutenberg.org/ebooks/43394}}
*{{cite web |author=Roberts Rinehart, Mary |title=Tenting To-night: A Chronicle of Sport and Adventure in Glacier Park and the Cascade Mountains |date=April 1918 |url=http://www.gutenberg.org/files/19475/19475-h/19475-h.htm}}

==External links==
{{Sister project links|wikt=no|commons=Glacier National Park|b=no|n=no|q=no|s=no|v=no|voy=Glacier National Park (Montana)|species=no|d=no}}
*{{Official website}} at the [[National Park Service]]
*[https://archiveswest.orbiscascade.org/ark:/80444/xv03780 Glacier National Park (Mont.) Collection, 1910–1953] at [[Archives West]]
*[https://glacierinstitute.org/ The Glacier Institute]
*[https://watch.montanapbs.org/video/montanapbs-presents-glacier-park-remembered/ ''Glacier Park Remembered''], a documentary produced by [[Montana PBS]]
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[[Category:Glacier National Park (U.S.)| ]]
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