Back Creek is a 59.5-mile-long (95.8 km)[1] tributary of the Potomac River that flows north from Frederick County, Virginia, to Berkeley County in West Virginia's Eastern Panhandle. Back Creek originates along Frederick County's border with Hampshire County, West Virginia, at Farmer's Gap in the Great North Mountain. Its name reflects its location to the west of North Mountain. The perspective of colonists from the east in the 18th century led them to call it "Back Creek", because it lay to the back of North Mountain.