Columnar joints in the Black Hand Sandstone of the Cuyahoga Formation that forms Old Man's Cave at Hocking Hills State Park, Hocking County, Ohio. Old Man's Cave is a large rock shelter in the northwest valley wall of Old Man's Creek. It is formed in the weakly cemented crossbedded middle zone of the Black Hand Sandstone. The rock shelter cave is about 200 feet long, 50 feet high, and 75 feet deep. The resistant uppermost zone of the Black Hand sandstone forms the roof of the cave. Bedrock is from the Mississippian Geologic Period.