The 7 Best Caves and Caverns to Visit in the U.S.

The United States has an overwhelming amount of beautiful natural landmarks - waterfalls, mountains, massive lakes, clear oceans, booming rivers, lush forests, and tropical swamps - but one sometimes goes forgotten; caverns!

Have you ever gone deep underground to see what lurks in the worlds below us? Caves and caverns are just as big a part of the U.S.'s natural wonders, and we've come up with our list of the 8 best caves and caverns in the U.S.

1. Meramec Caverns, Missouri - This nearly 5-mile cave system is most famous for being the hide-out of Westerner Jesse James, and today it keeps up the tradition with other fact-or-fiction storytellings like Tom Sawyer and Becky Thatcher out-running Injun Joe in re-enacted tours. With more than 6,000 caves in the system, 23 offer walking tours, which, at a cool 60 degrees, are great for a hot summer day.

2. Carlsbad Caverns, New Mexico - Perhaps the most famous of America's caves, Carlsbad Caverns is usually referred to as "the Grand Canyon with a roof on top" due to its extreme beauty and depth. The "big room" is the most sought-after spot, with millions of strange formations dangling from the ceiling. The deepest chamber is more than 1,000 feet below the surface.

3. Luray Caverns, Virginia - If ten-story high ceilings in cathedral-sized rooms sound up your alley, head to the Shenandoah Valley to explore Luray Caverns! Here exists the world's only stalactite pipe organ, which creates haunting, echoed music when hitting with rubber mallets provided on the tours. Be sure to Frozen Fountain, made of transparent, crystalline limestone.

4. Mammoth Cave, Kentucky - How does a cave get such a big name? By having nearly 300 miles of underground systems! Mammoth Cave allows visitors to participate in spelunking, and more intense visitors can take a "Wild" tour which allows them to crawl through muddy tunnels and dusty turns, through new labyrinths throughout the cave.

5. Caverns of Sonora, Texas - It might not be the largest, but the Caverns of Sonora are a tough contender for the most beautiful caves. Hundreds of pink and rose-colored stalactites and stalagmites grow from the floors, the ceilings, and even on the walls of the caves, making visitors feel like they're looking through the rose-colored glass at every turn.

6. Niagara Cave, Minnesota - Named after the 60-foot waterfall inside it, this beautiful cave is filled with stalactites, calcite flow-stones, and fossils that are over 400 million years old. Visitors can walk through echo-chambers, Paul Bunyan's Bed, and even get married in a small cave chapel!

7. Jewel Cave, South Dakota - If you're looking for a safe, ranger-guided tour through narrow passageways filled with calcite formations, such as stalactites, stalagmites, flowstone, and frostwork, South Dakota's 157-mile Jewel Cave may be the perfect stop! Check out the bizarre hydromagnesite balloon, made of crystallized mineral bubbles.