Mammoth Cave National Park United States

Legendary

Explore the beauty of the world's longest known cave system.

Photo by James St. John

Kid Rating:

In 1842, an enslaved man named Stephen Bishop sat down and drew a map of Mammoth Cave entirely from memory. It stayed the best map of the cave for more than forty years.

Bishop worked as a guide from the age of 17. He crossed a chasm called the Bottomless Pit on a ladder, found an underground river, and discovered eyeless fish swimming in it.

One thin line on his map pointed toward a passage nobody followed. It turned out to be the key to a puzzle that wouldn't be solved for 130 years.

The cave sits under the hills of central Kentucky, where the Green River winds through the park. Rainwater seeping down through the limestone has been carving passages here for millions of years.

People have explored it for a very long time. Native Americans mined minerals deep inside the cave thousands of years ago, and settlers dug it for saltpeter during the War of 1812.

Congress established Mammoth Cave National Park on July 1, 1941. At that point, the cave was thought to be about 40 miles long.

Meanwhile, cavers were mapping a separate system under Flint Ridge to the north. By 1972 it had passed Mammoth as the longest known cave in the world.

Explorers suspected the two were connected. On September 9, 1972, a team of six entered Flint Ridge and crawled, waded, and squeezed for twelve hours.

They came out into a passage they recognized as Mammoth Cave. Bishop's forgotten line on the map had been right all along.

Joining the two made it the longest cave system on Earth, at 144 miles. Since then, explorers have mapped more than 420 miles, and nobody knows where it ends.

The cave holds strange life too. Eyeless, colorless shrimp and fish live in its rivers, and several species of bats sleep on its ceilings.

Take a ranger-led tour, since that's the only way underground, and pick one that matches your family's comfort with tight spaces. Look for the signatures written on cave walls in candle smoke by visitors from the 1800s. Stay above ground after dark, because the park is also a certified Dark Sky Park.