Back Creek is a tributary of the Potomac River that flows north from Frederick County, Virginia to Berkeley County in West Virginia's Eastern Panhandle. Back Creek's source lies 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 from the east in the 18th century made it the "Back Creek" because it was lying to the back of North Mountain.