The natural history of this region is as fascinating as the caves are beautiful. Here, in these sandstones and shales, one can read Ohio's history from the rocks. The scenic features of the 6 areas of the Hocking Hills State Park complex are carved in the Blackhand sandstone. This bedrock was deposited more than 350 million years ago as a delta in the warm shallow sea which covered Ohio at that time. Subsequent millions of years of uplift and stream erosion created the awesome beauty seen today. The recess caves at Ash Cave, Old Man's Cave and Cantwell Cliffs are carved from sandstone. Weathering and erosion widened cracks found in the middle layer of sandstone at the Rock House to create that unusual formation. Other features of the rock include cross-bedding (noticeable as diagonal lines in the rock intersecting horizontal ones), honeycomb weathering (looks like the small holes in a beehive comb) and slump blocks. The huge slump blocks of rock littering the streams tumble from near by cliffs when cracks widen to the extent that the block is no longer supported by the main cliff.


Hike through this park to learn about its unique geological features.