Mammoth Cave is great, but there are other Kentucky caves to explore. Here's 5 of them

National parks. It seems post-COVID, we can't get enough of the outdoors and the natural beauty of America.

Kentucky boasts one national park (Mammoth Cave) and two national historical parks (Abraham Lincoln's Birthplace and Cumberland Gap), as well as national historic trails and national monuments.

Here in Kentucky, the excitement of an underground adventure doesn't have to end after the bus at Mammoth Cave National Park drops tourists back off at the visitors center.

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Here are five caves to visit near the national park that aren't part of the park, plus a surprise cave for an Eastern Kentucky adventure:

Hidden River Cave

County: Hart

Address: 119 E Main St., Horse Cave, Ky.

Once the site of severe contamination with untreated sewage and trash, Hidden River Cave used to be one of the most polluted underground sites in America. The cave has undergone a transformation thanks to the American Cave Conservation Association (ACCA), which is headquartered in Hart County and dedicated to cleaning up and protecting caves. Today, this cave is more than the site of clean drips and domes. It also has the longest underground swinging bridge in the world.

Lost River Cave

Lost River Cave is a 72-acre park that offers cave tours by boat. It also has a network of walking trails, a butterfly garden and more.

County: Warren

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Address: 2818 Nashville Road, Bowling Green, Ky.

Lost River Cave is a 7-mile cave system with a history that includes Civil War encampments, Native American hunting ground, Jesse James' hideout and an "Underground Nite Club" from the 1930s. The cave, located off Exit 22 of Interstate 65, has one of the largest cave openings in the Eastern United States. It's historic underground boat tours run year-round.

Crystal Onyx Cave

County: Barren

Address: 425 Prewitts Knob Road, Cave City, Ky.

This family-owned and operated cave, located on Prewitts Knob, is one of several private caves near the national park. The cave's website bills it as a small group tour with a comfortable pace and plenty of stops "so you can see all of nature's wonders, take pictures, relax and enjoy."

Mammoth Onyx Cave

County: Hart

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Address: 3700 L&N Turnpike Road, Horse Cave, Ky.

This cave is part of Kentucky Down Under Adventure Zoo, located in Horse Cave. The cave was discovered in 1799 but didn't open for public tours until 1922, according to its website. Tours are scheduled throughout the day at a leisurely pace. The cave contains 144 steps, and visitors will learn about the difference between cave popcorn and cave cauliflower. The cost of the 30-minute tour also includes animal exhibits, featuring attractions such as kangaroos and cockatoos.

Onyx Cave

County: Barren

Address: 93 Huckleberry Knob Road, Cave City, Ky.

Not to be confused with Crystal Onyx or Mammoth Onyx, this cave is just known as Onyx Cave. The cave was found during the construction of a parking lot in 1971 and opened as a show cave to the public in 1973. Originally, Cleon Turner developed and managed this cave and Crystal Onyx Cave, which is why the two caves share similar names, according to the cave's website. Today, the cave offers 30-35 minute tours with about 60 steps and includes a "Waterfall Wall," "Drippy Room" and "Big Column." It's located off I-65 at exit 53 and includes a rock shop.

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And now for your surprise "cave":

The Gorge Underground

County: Wolfe

Address: 2478 Glencairn Road, Rogers, Ky.

The Red River Gorge may have world-class climbing, but this Eastern Kentucky adventure involves less chalk and way more water. You can boat, kayak or stand-up paddleboard your way through these cave-like formations that are part of a historic mine system near the Red. You can even navigate the waters in a clear LED paddleboard or see-through kayak that provides views of the hidden details in the water. The adventure is "fine for beginners," according to the Gorge Underground's website because there is "no wind, waves or current in the mine, so it is a gentle, easy paddle." Grab a helmet with a headlamp and get paddling!

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Stephanie Kuzydym is an enterprise and investigative sports reporter. Reach her [email protected] or@stephkuzy.

This article originally appeared on Louisville Courier Journal: Kentucky caves to explore outside of Mammoth Cave National Park