America’s landscapes don’t stop at mountains, coastlines, and deserts. Beneath your feet lies an entirely different world, one shaped over millions of years by water, lava, and time.
From the longest cave system on Earth to lava tubes frozen in time, underground waterfalls you reach by elevator, and caverns filled with music, lakes, and glowing formations, these places feel more like science fiction than real life.
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All 24 of these underground attractions in the United States are open to visitors, and every single one deserves a spot on your bucket list.
East Coast Underground Wonders
Howe Caverns – New York
Located in upstate New York, Howe Caverns offers one of the most immersive cave tours in the Northeast. Visitors travel through massive limestone corridors, echoing chambers, and winding passageways shaped over millions of years.
The guided tour includes a 1.25-mile walk, a quarter-mile boat ride on a subterranean river, and 139 stairs along the way. Highlights include towering boulders, cavernous galleries, and cool underground air that makes this a year-round favorite.
Lost River Caverns – Pennsylvania
Lost River Caverns lives up to its mysterious name. An underground river winds through the cave, sometimes disappearing entirely from view before reemerging deeper below ground.
Guided tours take visitors through twisting tunnels and hidden chambers while sharing the cave’s geological and historical significance. It’s a smaller cavern but packed with intrigue and atmosphere.
Pro Tip: Be sure to take a jacket with you, as it can get chilly in the caverns.
Luray Caverns – Virginia
Luray Caverns has been welcoming visitors since 1878, but its most famous attraction arrived decades later.
In 1957, a mathematician created the Great Stalacpipe Organ, wiring 37 stalactites to a keyboard so they could be played like a musical instrument. Today, music echoes through 3.5 acres of cavern, making this one of the most unique cave experiences anywhere in the world.
Kentucky & Tennessee Cave Adventures
Mammoth Cave National Park – Kentucky
Mammoth Cave isn’t just big- it’s the longest known cave system on Earth, with more than 420 miles of explored passages and counting.
Tours range from easy, paved walks to physically demanding crawls through narrow passages. Some routes open into rooms five stories tall, while others shrink to shoulder-width squeezes. No two tours feel the same.
Pro Tip: Before you book a tour for any cave, do your research and make sure you can handle the physical aspects of the tour. If you do have some limitations, then look into options that aren’t as demanding.
Hidden River Cave – Kentucky
Hidden River Cave features one of Kentucky’s largest cave entrances and two underground rivers flowing more than 100 feet below ground.
Visitors cross the world’s longest underground swinging bridge and explore Sunset Dome, one of the largest free-standing cave domes in the United States. This cave combines dramatic scale with jaw-dropping geology.
Cumberland Caverns – Tennessee
Cumberland Caverns blends natural beauty with an unexpected twist: live music.
The cave’s Volcano Room hosts underground concerts known for their incredible acoustics. Even without a show, the cave’s formations alone make it worth visiting, but if you can catch a concert, it’s unforgettable.
Pro Tip: Whatever you do, don’t forget your camera. You’ll want to go back to these pictures. I’ve noticed things in pictures that I didn’t even remember from our trip. You’ll want one that takes videos too for when you head somewhere like Cumberland Caverns to catch the music. Check out the PixPro from Kodak on Amazon. We really like ours and it takes great videos.
Lost Sea Adventure – Tennessee
Home to America’s largest underground lake, the Lost Sea offers a rare cave experience -going by boat.
After walking deep underground, visitors board glass-bottom boats that glide across crystal-clear water. Trout swim below while massive rock walls disappear into darkness above.
Tuckaleechee Caverns – Tennessee
Near the Great Smoky Mountains, Tuckaleechee Caverns is known for its massive Big Room, one of the largest underground chambers in the eastern U.S.
Guided tours highlight towering formations, delicate mineral features, and the slow geological processes that shaped the cave over centuries.
Ruby Falls – Tennessee
Ruby Falls is reached by elevator, descending 260 feet into Lookout Mountain before walking through a cave passage to the waterfall.
The 145-foot underground waterfall is the tallest open to the public in the United States and is illuminated by shifting colored lights. It was discovered accidentally in 1928 while drilling an elevator shaft.
Mid-America Underground Attractions
Indiana Caverns – Indiana
Part of the Binkley Cave System, Indiana Caverns features ancient formations and an underground river explored by boat.
The combination of walking passages and boat tours gives visitors a varied and adventurous underground experience.
Meramec Caverns – Missouri
Meramec Caverns became famous thanks to a massive roadside advertising campaign in the 1930s, over 300 barn roofs once pointed travelers here, now billboards lead the way.
The cave drops seven stories deep and includes the colorful Stage Curtain formation. Legends claim Jesse James once hid here, though historians remain skeptical.
Blanchard Springs Caverns – Arkansas
Unlike many caves, Blanchard Springs Caverns is still actively forming.
Water continues to deposit minerals on formations that began growing 350 million years ago. Two tour levels showcase massive flowstones, rimstone dams, and columns still in progress.
Wind Cave National Park – South Dakota
Wind Cave is famous for boxwork formations, thin calcite fins that resemble honeycomb. About 95% of the world’s known boxwork is found here.
The cave also “breathes,” with air flowing in and out depending on barometric pressure. Above ground, bison and elk roam the surrounding prairie.
Pro Tip: Be sure to give yourself time to explore the park outside. This is one of the best parks to see bison and elk. Plus, the Black Hills area is beautiful.
Jewel Cave National Monument – South Dakota
With more than 200 miles of mapped passages, Jewel Cave is one of the longest cave systems in the world.
Calcite crystals coat the walls, sparkling under tour lights. Tours range from easy walks to longer explorations showcasing boxwork, spar crystals, and delicate formations.
Southwest Cave Experiences
Caverns of Sonora – Texas
Caverns of Sonora is famous for its rare helictites, delicate formations that twist in seemingly impossible directions.
Vibrant colors and intricate mineral patterns make this one of the most visually striking caves in Texas.
Carlsbad Caverns National Park – New Mexico
Every summer evening, visitors gather at an outdoor amphitheater to watch something you won’t see anywhere else. Around sunset, hundreds of thousands of Brazilian free-tailed bats spiral out of the cave entrance in a swirling column that can last over an hour. It is really mesmerizing.
During the day, visitors can descend into the Big Room, one of the largest underground chambers in North America, with ceilings reaching 255 feet high.
Pro Tip: Take night vision binoculars and you’ll be able to see and take pictures of the bats even after the sunsets. We like these from HEXEUM, they are easy to use and take great pictures.
Kartchner Caverns State Park – Arizona
Discovered in 1974, Kartchner Caverns remained secret for years to protect its pristine, living formations.
Opened to the public in 1999, the cave features two massive rooms, and the park carefully controls airflow and humidity to keep the formations alive. Reservations are strongly recommended.
Timpanogos Cave National Monument – Utah
High in Utah’s Wasatch Mountains, Timpanogos Cave is known for its colorful formations and dramatic alpine setting.
Guided tours lead visitors through vibrant chambers while sharing the cave’s geological and historical significance.
Glenwood Caverns – Colorado
Discovered in the late 1800s, Glenwood Caverns feature classic formations like stalactites, flowstones, and cave bacon.
Today, the caves are part of a mountain-top adventure park, offering both underground tours and above-ground thrills.
Lehman Caves – Nevada
Located in Great Basin National Park, Lehman Caves showcases rare formations like the Parachute Shield.
Delicate stalactites and intricate speleothems fill the chambers, making this one of Nevada’s most underrated underground attractions.
West Coast Underground Wonders
Moaning Cavern – California
Moaning Cavern is known for its massive chamber and eerie sounds caused by dripping water echoing through the cave.
Visitors can descend via spiral staircase, rappel into the cavern, or explore its archaeological history dating back thousands of years.
Lava River Cave – Oregon
Formed 80,000 years ago, Lava River Cave is a mile-long lava tube with year-round temperatures around 42°F.
Ice sometimes clings to the walls near the entrance in early summer. Flashlights and warm layers are essential, even in August.
Oregon Caves National Monument – Oregon
Deep within the Siskiyou Mountains are dark, twisting passages that await your discovery. Eons of acidic water seeping into marble rock created and decorated the wondrous “Marble Halls of Oregon”.
The 90-minute tour includes more than 500 stairs, and the historic lodge above ground is worth visiting too. The Chateau is closed for renovations as of this writing but expects to open soon. Check the NPS website for more information.
Ape Cave – Washington
Ape Cave is the longest lava tube in the continental United States, formed by Mount St. Helens nearly 2,000 years ago.
The lower passage offers an easy walk suitable for families, while the upper passage challenges visitors with boulders, scrambling, and tight squeezes.
Final Thoughts: America’s Hidden Underground World
The United States is home to some of the most diverse and accessible underground landscapes in the world. From musical stalactites to lava tubes and massive cave systems still being explored, these destinations prove that adventure doesn’t always happen above ground.
Whether you’re a casual traveler or a full-on cave nerd, these underground wonders offer unforgettable experiences and a whole new appreciation for what lies beneath your feet.