South Mountain is a 2,185-foot summit in the Catskills of Ulster County, New York, forming part of a massif with Ashokan High Point, Mombaccus Mountain, and Little Rocky. Its slopes shape the local terrain, falling northwest toward Watson Hollow, southwest to South Hollow, and rising on the east above High Point Mountain Road in West Shokan, within the town of Olive. A notable modern feature stands on the ridge just north of the summit: a cell phone tower built on private property after a 2005 court ruling against the town of Olive.