Editing Endless Mountains (section)

==Geography==
{{See also|Geography of Pennsylvania}}
[[File:Elkmountaintop.JPG|thumb|The Endless Mountains seen from [[Elk Mountain Ski Area]] in [[Herrick Township, Susquehanna County, Pennsylvania|Herrick Township]]]]
Part of the [[Appalachian Mountains]] chain, the region does not consist of true mountains, [[geology|geologically]] speaking, but instead a [[dissected plateau]] that is part of the [[Allegheny Plateau]]. The [[Catskill Mountains]] are the highest expression of the plateau, located to the east of the Endless Mountains, and separated from them by the [[Delaware River]].

The current geography was slightly modified during the last [[ice age]] by the [[Wisconsin Glacier]] about 15,000 years ago. [[Glacial striation]]s can be found on the [[rock (geology)|rocks]] of some of the high ridges, but the area was at the margin of the ice sheet, and the impact was much less than in [[New York (state)|New York]] just to the north.

The mountains are made up of [[sedimentary rock]]s (mostly [[sandstone]] and [[shale]]s, with a little [[conglomerate (geology)|conglomerate]]) that were part of a lowland that collected sediments [[erosion|eroded]] from mountains to the southeast in [[Mississippian age|Mississippian]] and [[Pennsylvanian (geology)|Pennsylvanian]] geologic time. The area has been uplifted and lowered several times. The highest points are all nearly the same elevation, establishing that the area had once been eroded into a nearly level [[peneplain]], which has since been uplifted. The present [[Susquehanna River]] established its [[meander]]ing course during that time, when it was a mature stream on a topography of very low relief. When the area was uplifted, the river's bends were preserved as [[incised meander]]s. The large river cut a deep valley and established a low baseline for its [[tributary|tributaries]], which then cut the plateau into the rugged hills of the present day.