The large square and circle enclosure at the Hopeton works are some of the largest of their kind and were used in conjunction with Mound City across the Scioto River. Recent research has shown the circular portion had a large ring of wooden posts mounted in the earthworks, making the Hopeton site the largest woodhenge in the world.
Inside the 'caviest cave in the US', a multi-level limestone fracture cave
One of Ohio's greatest mysteries... the old mistry river reaches the seventh level of Seneca Caverns and feeds the famous Blue Hole at Castalia. Still unknown... the true extent of the underground river system in northwest Ohio which feeds numerous caves and springs and eventually drains to Lake Erie.