View source for Elfas

{{short description|Hill range in Germany}}
{{Infobox mountain range
| name = Elfas
| map_image = Reliefkarte Homburg, Elfas, Holzberg, Amtsberge.png
| map_caption = The Elfas between [[Stadtoldendorf]] and [[Einbeck]]
| photo = lowsaxlandscd.jpg
| photo_caption = The Elfas from the south
| state = Counties of [[Landkreis Holzminden|Holzminden]] and [[Landkreis Northeim|Northeim]]; [[Lower Saxony]] {{GER}}
| parent = [[Leine Uplands]], [[Lower Saxon Hills]]
| location = 
| geology = [[Sandstone]]
| period = [[Bunter sandstone]]
| area_km2 = 
| orogeny = 
| highest = [[Helleberg (Elfas)|Helleberg]]
| elevation = {{Höhe|409.6|DE-NHN}}
| coordinates = 
| length_km = 
| range_coordinates = {{coord|51.870|N|9.7333|E|region:DE_type:mountain_scale:300000|format=dms|display=inline,title}}
}}
The '''Elfas''' is a range of hills up to {{Höhe|409.6|DE-NN|link=true}}{{GeoQuelle|DE|BFN-Karten}}  in the districts of [[Landkreis Holzminden|Holzminden]] and [[Northeim (district)|Northeim]] in [[Lower Saxony]] ([[Germany]]). Its name is derived from the [[Eastphalian dialect|Lower Saxon]] word ''Fast'', which means an area of upland that descends on two sides.<ref name="GSchambach" />

== Geographical location ==
The Elfas is located in the middle of the [[Leine Uplands]] between the [[Hils]] to the north, the [[Homburg Forest]] to the west, the [[Hube (hills)|Hube]] to the east, the [[Amtsberge]] to the south-southwest and the [[Holzberg]] to the southwest. It lies not far southwest of [[Eschershausen]] and east of [[Stadtoldendorf]]; the town of [[Einbeck]] is about 12&nbsp;km southeast of the Elfas. The [[Bundesstraße 64|B&nbsp;64]] federal highway runs past the Elfas to the north linking Eschershausen with Einbeck.

The rounded summits of the Elfas are covered by [[acidic soil]] [[Beech|beech forests]].

== Geology ==
The Elfas is mainly composed of [[sandstone]]s from the [[Bunter sandstone]] period. As the result of a [[Halokinesis|halokinetic]] process, which had already been concluded in the [[Palaeogene]] period, the Elfas [[fault block]] migrated in a north-easterly direction towards the [[Solling]], whereby the mountain-building sandstone rode up over a layer of [[saliniferous rock]] of the [[Zechstein]]. In the course of this process, mainly older rock strata that had hitherto lain underneath, were overthrust. Out of the subsequent erosion processes today's [[scarpland]] emerged as the northern boundary of the [[Einbeck-Markoldendorf Basin]].<ref name="AHerrmann" />

Geologists in the Weser Uplands also use the terms Elfas Axis (''Elfas-Achse'') or Elfas Fault (''Elfas-Überschiebung'') for the regional fault line, as well as the term ''Elfas Saddle''.

== Hills ==
The hills in the Elfas include (heights in metres above [[Normalnull|NN]]{{GeoQuelle|DE|BFN-Karten}}):
{{colbegin}}
* [[Helleberg (hills)|Helleberg]] (409.6 m)
* Ahrensberg (405 m)
* Kneppelberg (386.0 m)
* Birkenberg (366.4 m)
* Vorwohler Berg (360.2 m)
* Moosberg (344.7 m)
* Eichholzberg (341.5 m)
* Döhrenberg (307.1 m)
* Eimer Berg (ca. 300 m)
* Kurzeberg (299.0 m)
* Böhneberg (290.0 m)
* Heisennacken (267.0 m)
{{colend}}

== Streams ==
The streams of the Elfas include: 
* Allerbach (eastern tributary of the Bewer) 
* [[Bewer]] (northern tributary of the [[Ilme]]) 
* Hillebach (northern tributary of the [[Krummes Wasser]]) 
* [[Lenne (Weser)|Lenne]] (passes the Elfas to the west)

== References ==
<references>
<ref name="GSchambach">Georg Schambach: [https://books.google.com/books?id=0YUCAAAAQAAJ&dq=fersengeld+w%C3%B6rterbuch&pg=PA257 Wörterbuch der niederdeutschen Mundart], 1858, p.&nbsp;257</ref>
<!---->
<ref name="AHerrmann">Axel Herrmann, Carsten Hinze, Volker Stein: ''Die halokinetische Deutung der Elfas-Überschiebung im südniedersächsischen Bergland'', in: ''Geologisches Jahrbuch&nbsp;84'', 1967, pp.&nbsp;407ff.</ref>
</references>


[[Category:Central Uplands]]
[[Category:Hill ranges of Lower Saxony]]
[[Category:Natural regions of the Weser-Leine Uplands]]
[[Category:Holzminden (district)]]
[[Category:Northeim (district)]]