Elk Ridge is a mountain ridge of the Blue Ridge Mountains in Maryland. The ridge is located to the west of South Mountain and runs roughly parallel to it from Rohrersville, in the north, to the Potomac River across from Harpers Ferry, West Virginia, in the south. Across the Potomac the ridge continues as Blue Ridge Mountain in Virginia and West Virginia. The southern end of the ridge, which is part of Harpers Ferry National Historical Park, is known as Maryland Heights.