Mammoth Cave (2023, on hiatus)
Mammoth Cave, a roughly 426-mile* system of underground passageways in Central Kentucky, is the longest in the world — and it's still getting bigger. Year round, volunteers with the Central Kentucky Karst Coalition, Cave Research Foundation and National Park System work together to survey the full undiscovered length of the cave, which is estimated to be up to 1,000 miles.
Holly McClintock, President of the Central Kentucky Karst Coalition, is a caver who leads surveying trips into sections of Mammoth Cave, including Roppel Cave, that contain possibilities of new discovery, called leads. It's a long and muddy process where by the end of the trip, the cavers and everything they carry with them is waterlogged.
Once a month throughout the year, along with other volunteers, Holly hikes, climbs and crawls through tight squeezes and wide tunnels for as long as 30 hours at a time, searching for the next big connection.
*This mileage of Mammoth Cave was written after a caving expedition in 2022 — the length has likely grown since then.
