Cave
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Mammoth Cave
Mammoth Cave in Kentucky is the world's longest known cave system, spanning over 420 miles of surveyed subterranean passageways. Steeped in thousands of years of human history—from Native American mineral gatherers and War of 1812 saltpeter miners to an ill-fated 19th-century consumption hospital—this subterranean realm holds a legendary reputation for subterranean ghost sightings and disembodied voices.