Meramec Caverns

Meramec Caverns is a 4.6 mile cavern system in the Ozarks near Stanton, Missouri, and it is the most visited cave in the state, with something like 150,000 people a year going through it.

It has been forming for around 400 million years as water dissolved out the limestone. Native Americans used it for shelter, and pre-Columbian artefacts have been found inside. It has one distinction no other cave west of the Mississippi can claim: it was the first to be explored by Europeans, visited in 1722 by a French miner.

Saltpetre was extracted here through the eighteenth century, and during the Civil War the Union Army ran a saltpetre plant in the cave. Confederate guerrillas found it and destroyed it, and the raiding party very likely included a young Jesse James.

That is where history stops and the billboards take over. Local legend has James and his brother Frank using the caves as a hideout in the 1870s, with a story about a sheriff waiting outside while the gang escaped another way. There is scant historical evidence for any of it, and the cave has never let that get in the way. More than fifty billboards line Interstate 44, and the place is one of the definitive attractions of old Route 66, which is a genuine piece of Americana whatever the Jesse James business is worth.

Tours are guided, run year round, and finish in a large chamber with a light show projected onto a wall of flowstone.

The cave as visitors know it dates from 1933, when the extended system was found, taking it to its present 4.6 miles. Lester B. Dill opened that to the public in 1935 and then did something that outlived the cave in cultural terms: to advertise it, he invented the bumper sticker. In 1960 he went further and rented out billboard space inside the caverns, claiming the only underground billboard in the world.

The fifth level holds the Wine Room, named for the botryoids, grape-like mineral clusters, growing through it. Its centrepiece is the Wine Table, an aragonite formation about six feet high standing on three natural legs, formed almost entirely underwater and billed as the rarest cave formation anywhere. It costs 58 steps to reach it, which the cave now says is the real reason the room is called the Wine Room.