Wills Mountain is a long quartzite-capped ridge in the Appalachian Ridge and Valley, extending from near Bedford, Pennsylvania, to near Cumberland, Maryland. It is the northernmost ridge of the Wills Mountain Anticline, a major folded rock structure that continues south into West Virginia and Virginia. In Pennsylvania it reaches 2,782 feet, the highest mountain in that state's Ridge and Valley province. Its hard Tuscarora quartzite crest has resisted erosion while softer surrounding rocks wore away, a geology clearly seen at the Cumberland Narrows, where Wills Creek cut a water gap. That passage later became an important western route for roads and rail lines, while much of the ridge has remained comparatively undeveloped.

Photo: Wikipedia · Public domain

Photo: Wikipedia · Public domain

Photo: Wikipedia · Public domain

Londonderry Township, Pennsylvania · USA