2,316 ft (706 m) NAVD 88
40°2′52″N 77°45′2″W / 40.04778°N 77.75056°W / 40.04778; -77.75056Coordinates: 40°2′52″N 77°45′2″W / 40.04778°N 77.75056°W / 40.04778; -77.75056 
Location of Clarks Knob
Franklin County, Pennsylvania, U.S.
Blue Mountain 
USGS Roxbury (PA) Quadrangle 
Drive up gravel road 
Clarks Knob is a summit in Franklin County, Pennsylvania. It is the highest point on Blue Mountain, the eastern front range of Pennsylvania’s Ridge and Valley Appalachians region.
Clarks Knob’s northeast-southwest running summit ridge forms the boundary of the Susquehanna River and Potomac River drainages. It stands over 1,600 feet (488 m) above the town of Chambersburg and the Great Appalachian Valley. This mountain is protected within the Buchanan State Forest.
^ a b c “Clarks Knob”. NGS data sheet. U.S. National Geodetic Survey. Retrieved 2009-02-08.
^ a b c d e “Clarks Knob, Pennsylvania”. Peakbagger.com. Retrieved 2009-02-07.
^ “Clarks Knob”. Geographic Names Information System. United States Geological Survey. Retrieved 2009-02-08.