Six hundred and fifty feet under Hutchinson, in one of the largest rock salt deposits on earth, and the ONLY salt mine in the United States you can go down into as a visitor. A double-deck elevator carries fifteen people a level and takes about ninety seconds to drop you; a tram runs the dark chambers beyond the lit galleries. It has been a museum since 2007. Nothing decays down here, which is why studios store film in the workings. PUBLIC, Hutchinson, Kansas.
Kansas
See it on the map
Other places on the map within a couple of hours.