You swim into this one. A river passage runs about two miles back under the Tapir Mountain Nature Reserve before it sumps, and above it another mile of dry chambers holds what the Maya left: pottery punched with kill holes to let the spirit out, one of only four Monkey Pots ever found in Central America, and skeletons. The famous one is called the Crystal Maiden, thought to be a boy of about seventeen, almost certainly a sacrifice, whose bones have taken on a sparkling crystalline crust from centuries of dripping mineral water. NO CAMERAS without a permit since 2012, after a tourist dropped one on an ancient skull, and you go through the dry chamber in socks. Closes when the rain floods it. Guided only, Cayo District.
Mexico
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