14 Incredible U.S. Caves You’ll Never Forget Once You Visit
Most people think of visiting big cities, national parks, and beaches when they plan a U.S. trip. There’s hardly anyone who’s wondering what’s underground. The caves in the U.S. are where things get surprisingly wild. The country is home to some of the most unique and record-breaking caves in the world, from crystal chambers to hidden lakes beneath the surface.
Let’s learn more about these incredible places below.
Mammoth Cave – Kentucky
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You could spend weeks down here and still not see it all. Mammoth Cave is the longest cave system in the world, with over 426 miles mapped so far. There are guided tours that range from easy walks to lantern-lit treks. It’s also home to rare cave wildlife and ancient mining history.
Carlsbad Caverns – New Mexico
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The real show at Carlsbad starts when the sun goes down. Every summer evening, thousands of bats swirl out of its entrance in a dramatic flight. Inside, you’ll find chambers the size of city blocks shaped by sulfuric acid instead of water.
Luray Caverns – Virginia
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Do you know any other cave that plays music? Luray’s Great Stalacpipe Organ uses rubber mallets to tap stalactites and create real notes across the cave. Beyond the novelty, it’s packed with towering formations, crystal-clear pools, and easy, paved walkways—perfect for travelers who want beauty without a strenuous hike.
Jewel Cave – South Dakota
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This cave’s name is no exaggeration. Jewel Cave glitters with crystals that coat the walls like frost. It’s the third-longest cave system in the world, with over 200 miles explored. Tours cover everything from scenic strolls to crawling through tight spaces with a helmet and headlamp.
Wind Cave – South Dakota
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Not all caves look the same—and Wind Cave proves it. It’s known for a strange, fragile formation called boxwork, which looks like cracked glass or stone honeycomb. The cave is one of the world’s most complex, and above ground, bison and elk roam the national park’s open prairies.
Kartchner Caverns – Arizona
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For 14 years, no one knew this cave existed—except the two guys who found it and kept it secret to protect it. Kartchner opened to the public in 1999 and still feels untouched. Inside, you’ll find the world’s longest soda straw and living formations that are still growing.
Natural Bridge Caverns – Texas
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Before you even step inside, the view of Natural Bridge is super impressive. A natural limestone bridge arches above the cave entrance and gives this spot its name. Tours lead you through wide chambers filled with towering columns. It’s just outside San Antonio, and the site includes rope courses, mining activities, and zip lines.
Ruby Falls – Tennessee
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This one takes you to the heart of a mountain. Ruby Falls lies 1,120 feet inside Lookout Mountain and ends in a 145-foot underground waterfall. It was discovered in the 1920s when an elevator shaft led to the cave system. Today, it’s a favorite for travelers heading through Chattanooga.
Longhorn Cavern – Texas
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During Prohibition, this place doubled as a secret dance hall. Before that, it was used by Native tribes—and maybe even outlaws. Longhorn Cavern’s smooth tunnels were carved by an ancient river. Its tours mix history, geology, and a few ghost stories locals still love to tell.
Meramec Caverns – Missouri
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People have been visiting these caves since the 1930s—and not just for the cool air. Meramec sits right off Route 66 and offers a mix of massive formations and old-school charm. Highlights include the “Wine Table” and a towering room called the “Mansion.”
Ohio Caverns – Ohio
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Color isn’t something most caves are known for, but these walls break the mold. Ohio Caverns are full of rich mineral tones—orange, blue, and snow white. The star of the show is the Crystal King, a six-foot stalactite that’s been forming for over 200,000 years.
Penn’s Cave – Pennsylvania
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No walking tour here—visitors can explore this cave by boat. Penn’s Cave is the only all-water cave in the country. The slow-moving ride passes beneath sculpted ceilings and glowing formations. Above ground, there’s a wildlife park with wolves, bears, and bison. It’s a great spot for families with curious kids.
Lost Sea Adventure – Tennessee
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A lake, hidden deep underground, stretching more than four acres across–That’s what you’ll find at the Lost Sea. The cave tour includes a boat ride on eerily still water and a look at rare anthodites—spiky, flower-shaped crystals found in only a few places on Earth.
Crystal Cave – California
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This cave isn’t open year-round, but if you’re heading to Sequoia National Park between June and August, it’s worth the stop. Crystal Cave is made of marble, not limestone, so the formations look smooth and glossy. It reopens in 2025 after wildfire repairs. Tickets go on sale on March 31.
Lehman Caves – Nevada
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Lehman Caves sits inside Great Basin National Park—one of the best stargazing spots in the U.S. Once underground, you’ll walk past rare shield formations and learn how marble, water, and time created these detailed rock textures.