A salt cavern in a mine in Hutchinson, Kansas. The long corridor leads to storage areas the the equal of 35 football fields. There is a gift shop, museum displays, and the electric train ride visitors can enjoy. The tunnels extend over 65 miles (104k) out in every direction. Visitors are required to wear a hard hat and have breathing apparatus ready in case of emergency. Access is via a utility freight elevator that rattles and bangs its way down 650 feet in total darkness...a thrilling way to begin the tour.