The show pony of cave systems, Fantastic Caverns manages to live up to its name.

This is not your typical jungle gym.

A creepy sculpture of a decapitated head invites viewers to see St. Louis through its empty eyes.

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

Community bookshelf of 25-foot-tall book spines.

Erosion and time have created a naturally-formed water park.

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

Curious cave that stays a cool 56 degrees all year long.

The history of the treatment of mental illness, illustrated in all its gory detail, and housed in an asylum.

This abandoned prison castle has become an imposing gallery of graffiti art.

Once an ambitious nature spa, these forest ruins now provide a serene monument to failure.

European castle ruins in an American state park are actually the product of death and grief.

Less a museum than a bizarre fantasy world created by artists and engineers.

A 35-foot-tall fork stuck in the ground outside an office building in Missouri.

Like Stonehenge, but with boats and oodles more charm.

A mysterious light of unknown origin on the backroads of Missouri.

This mosaic-covered bar is brimming with curated curios.

The maximum security facility was once thought to have "the bloodiest 47 acres in America."

If there's another drive-through golf-cart bar in a bat-filled cave on top of a mountain, we don't know about it.

Entombed in this strange, white stone hill are the deadly remains of radioactive weapons production.

A subterranean haunt where wine and homemade biscottis are always on the menu.

Speak to a companion on the other side of the room loud and clear through this architectural anomaly.

An unexpected but incredible collection of wildlife dioramas spanning rainforests, swamps, forests, and plains.

A kitschy, creepy St. Louis mainstay.