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 six 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