Seneca Caverns Registered Natural Landmark
Seneca Caverns is one of Ohio's largest underground caverns, and one of America's most fascinating geological wonders. Because it is so unique it is often referred to as "The Caviest Cave in the USA".
Inner Space Cavern
Inner Space cavern was discovered by a Texas Highway Department core drilling team in the Spring of 1963. Six inch core samples were taken to determine if the ground was stable enough to support a large highway overpass. As they were drilling one of the test holes, the bit suddenly dropped 26ft. and the highway crew knew there was something down there besides rock.