Hocking Hills State Park, for National Public Lands Day. Hocking Hills is a 2,356-acre park in southern Ohio offering over 25 miles of hiking trails that pass by unusual rock formations, recess caves, and stunning waterfalls. This is Upper Falls, at one of the park"s most popular hiking destinations, Old Man"s Cave. This huge recess cave, as the legend goes, was named for a hermit who lived here in the 1800s. Then there"s Devil"s Bathtub, Conkle"s Hollow, and Rock House—sites worthy of a visit for their names alone, though the scenery won"t disappoint.