Nationwide network of co-ownership underground catastrophe shelters.

This 1854 courthouse along the Mississippi River has a storied history.

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

A 40-foot waterfall flows into this unique natural swimming hole.

A historic, scenic mill that was forced to close due to overlogging.

An average of 33 million gallons of water pour out of the collapsed cave at the heart of this spherical spring.

Often referred to as the largest spring in America.

One of the deepest springs in Missouri.

A remarkably opulent mansion with a tragic history.

This otherworldly church spire reaches up toward the heavens.

A gem in the small Missouri town where Winston Churchill coined the term "Iron Curtain" and effectively began the Cold War.

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

Giant granite rocks standing end-to-end like a train of circus elephants.

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

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

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

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

A 22-foot stainless steel quilting needle pays tribute to a local connection to fiber arts.

A collection of outdoor art by renowned muralist Robert Dafford depicts the history of a flooded city.

This huge clock made of flowers and simple machinery was once used a political weapon.

This grave marks the final resting place of a legendary frontiersman... unless it doesn't.

A local scoured more than 1,000 acres for stone to create his masterpiece.

Prehistoric animals decorate this popular outdoor park.

One of the few surviving "Wigwam"-themed motels.