Caves

"The most colorful grottoes of the world.

The world's largest man-made underground caverns offer unparalleled underwater wonders.

The largest cave shaft in the world is home to thousands of birds and popular with BASE jumpers.

These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

This cave holds a surprisingly colorful variety of geological oddities.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

A small but industrious mining operation that allows visitors to touch precious gems while they are still in the rock.

A unique seaside cave where Aleister Crowley faked his own death.

Figures of unknown origin carved into the surfaces of underground caves.

The small cave that housed Tennessee's "first citizen."

The first full-scale tunnel built in America is short but scenic.

This series of Scottish caves has no clear purpose other than baffling historians.

This limestone cave offers an incredible view of the Río Grande de Arecibo valley.

Ancient rock-hewn town that witnessed key events of Georgian history.

In a long-dry lake bed, these groups of massive stone pillars bear a striking resemblance to clumps of everyone's favorite fungi.

The second-deepest known cave on Earth, hidden in an extremely remote mountain region.

The "World's Largest Underground Business Complex," a 55,000,000-square-foot city underneath Missouri.

400 million-year old limestone caverns nestled in the Ozarks served as shelter and a hideout for cultures throughout North American history.