Which US state is home to Mammoth Cave?

Mammoth Cave is in Kentucky, in the south-central United States. The cave lies within Mammoth Cave National Park, whose protected landscape spans parts of Edmonson, Hart and Barren counties.

Mammoth Cave is famous for being the longest known cave system in the world. More than 400 miles of passages have been surveyed, though exploration continues and the mapped total can change as new connections are found. Its passages developed in thick limestone shaped by groundwater over millions of years.

The cave has a long human history. Indigenous peoples used it before European-American settlement, and written accounts of exploration date to the late 18th century. In the 19th century, portions of the cave were mined for nitrate, a key ingredient in gunpowder.

Kentucky’s Mammoth Cave is not the same as Missouri’s Meramec Caverns or Virginia’s Luray Caverns. “Mammoth” refers to the cave’s immense extent, not to woolly mammoth fossils. The national park was established in 1941 and became a UNESCO World Heritage Site in 1981.