Our Pick
Posted on @rawstates
Meramec Caverns
1935
Franklin County, Missouri
T.sujatha · CC BY-SA 3.0 · Wikimedia Commons
Lester Dill opened a cave on Route 66 and effectively invented the bumper sticker to advertise it, having attendants fix them to cars while drivers were underground. He also claimed Jesse James used the cave as a hideout, on evidence nobody has ever produced.
That was 1 of the hidden places.
Location: documented spot
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