The World’s Longest Cave Is in Kentucky

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Many people associate the state of Kentucky with fried chicken, bourbon, horse races and farms. While all these things do define what Kentucky is about, there’s a lot more to this underrated state.

Honestly, Kentucky was never a destination of interest to me. That was, though, until we were on our way back to the East Coast after spending a month out West.

A passing-through state at first, Kentucky became a great stopping point for us in the end.

The reason was that, because we were on a national parks road trip, we figured it wouldn’t make sense if we just rushed through the state on the interstate, without visiting Mammoth Cave National Park, home to a collection of massive caves in Kentucky.

Longest Cave in the World

Kentucky, like other Appalachian states such as Virginia, West Virginia and Tennessee, is covered with woods and hills. There are rolling mountains, wide valleys, meandering rivers and tumbling waterfalls. The hiking trails are great, the landscapes beautiful.

I was pleasantly surprised by the woodsy character of Kentucky. To me, it shows that the state has more to offer than what its traditional image portrays. Hopefully, I can change your mind a little bit with this post as well.

Underneath those peaceful forests and undulating landscapes lies something that’s quite a surprise. This is the location of the longest cave in the world. There’s a lot of history—human and natural—to this place as well, but I won’t go too deeply into that. You can read it all here.

Mammoth Cave, actually a collection of linked cave systems, encompasses more than 400 miles (650 kilometers) of known passageways, halls and tunnels.

No other cave in the world comes even close to that massive size. In fact, Mammoth Cave in Kentucky is almost twice as long as the world’s second-largest cave system, which is the Sac Actun Cenotes in Mexico.

Even though it was given way before anyone realized its true enormity, the cave’s name, in other words, is appropriate.

World Heritage in Kentucky

Mammoth Cave became Mammoth Cave National Park in 1941. Forty years later, it was designated World Heritage by UNESCO, which is the most solid proof you can find for anything’s uniqueness, greatness and importance.

In the case of Mammoth Cave National Park, it stands out from all other environments on this planet not only because of its vastness, but also because of its delicate and fragile cave ecosystems, which depend almost entirely on what happens above ground.

This is why it’s so important to have the surface land protected as well. Mammoth Cave National Park does just that. It protects the entire cave system and some of the Green River valley and landscapes of south central Kentucky.

In 1990, the park also became an International Biosphere Reserve, again indicating and pointing out both the vulnerability and significance of this amazing place.

A Day in Mammoth Cave National Park

Although there are numerous fun hiking trails in the woods, the major attraction in this park is without question the caves.

Previously called “a grand, gloomy and peculiar place” by one of the cave’s earliest tourist guides, Stephen Bishop, Mammoth Cave is definitely impressive.

Guided (paid) ranger tours are the only way to see the caves. And there are many of those, too. In fact, there are almost twenty different cave tours on offer.

No matter how much time you can spend in Mammoth Cave National Park, you should do at least one of the cave tours. Frankly, it would be unacceptable to visit Mammoth Cave National Park without heading underground.

These tours range in duration from about twenty minutes to six hours, with pretty much everything in between. You have plenty of choice. This huge variety in Mammoth Cave tours ensures that people of all ages and abilities can see a part of this vast cave system.

Check Recreation.gov, the official booking website for most of the U.S. national parks’ tours and accommodations, for more information.

I strongly recommend reserving a spot in advance. Many tours sell out and you do not want to arrive at the park, walk up to the ticket booth and find out the day’s tours are all fully booked.

I did the Domes and Dripstones Tour, which involves a bus ride and lasts about two hours. It typically runs all day long.

This tour is a nice introduction to Mammoth Cave—the guide was great—and takes visitors through narrow passageways, underneath crumbling ceilings, across cave halls and past collections of stalagmites and stalactites—the dripstones.

When you pre-book your tour, you can simply pick up your ticket when you arrive. You’ll then have some time to explore the park’s visitor center. The exhibits are awesome and watching the film is mandatory.

After your tour, I suggest you head out on one of the trails around the visitor center. The River Styx Spring Trail combined with the Green River and Dixon Cave Trails makes for a nice woodsy loop.

Those landscapes above ground are an intricate part of Mammoth Cave National Park.

More Information: Mammoth Cave National Park

To get a complete understanding of this park, you need to go for an underground cave tour and an above-ground hike.

If you have more time, though, you might want to hit some of the park’s several backcountry trails. Bisected by rivers, it’s also a great place for canoeing and kayaking.

With its many miles of peaceful hiking trails, great rivers for boating, exceptional cave tours and excellent facilities, it’s actually a marvelous destination for a quiet camping vacation.

In case you’re just passing by on a road trip, like we were, spending a day in Mammoth Cave National Park is enough to get a grasp of what is extraordinary place is all about.

That day would look something like this:

• Arrival in the morning
• Pick up pre-booked tickets
• Visit exhibits and watch the park movie
• Go on a cave tour
• Explore the park’s woods on a hike
• Have dinner at one of the restaurants

Have You Ever Spent a Day in Mammoth Cave National Park? On Which Tour Did You Explore the Longest Cave in the World?