Mount Davis, in Forbes State Forest near Markleton, is Pennsylvania's highest point at 3,213 feet, occupying the broad crest of a long ridge that continues into Maryland as Negro Mountain. Named for John Nelson Davis, an early settler, Civil War veteran, surveyor, and naturalist, it was confirmed in 1921 by the U.S. Geological Survey as the state's highest peak, replacing Blue Knob. The summit area includes the Mount Davis Natural Area, an observation tower, and unusual circular stone patterns shaped by periglacial action. Its elevation gives it a notably cool climate, with mild summers, snowy winters, and frost recorded in every month.