Quirauk Mountain, in northeastern Washington County, Maryland, is the highest point on South Mountain at 2,145 feet. Near Cascade, Fort Ritchie, and Blue Mountain, it has long been important not only for its elevation but also for communications. Its summit carries a broadcast tower serving Hagerstown radio stations and includes Site C, a radio outpost tied to a United States Department of Defense emergency relocation facility near Blue Ridge Summit, Pennsylvania; part of the summit remains restricted federal property. Older structures reflect earlier uses, including a former fire lookout tower adapted from the Pen-Mar resort. Nearby High Rock adds to the mountain’s prominence in the South Mountain landscape.