Our Pick
Posted on @rawstates
Carlsbad Caverns
1930
Eddy County, New Mexico
Eric Guinther, User:Marshman · CC BY-SA 3.0 · Wikimedia Commons
A teenage cowboy followed what he thought was smoke and found it was hundreds of thousands of bats leaving a hole in the ground. The Big Room below is the largest single cave chamber in North America, dissolved by sulphuric acid rather than ordinary groundwater.
That was 1 of the hidden places.
Location: documented spot
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