Two massive and unstable sinkholes are yearning to unite, and their consummation could be catastrophic.

An abandoned mine where dreams of quicksilver trickled away over 75 years ago.

The second largest roadrunner in the world stands 11 feet tall in his West Texas town.

This old abandoned sign flickers to announce a motel that isn't even there.

Minimalist modern art on a repurposed military base in rural Texas.

This quirky outpost and gallery inside a former church is an unexpected trove of handcrafted art.

Mysterious glowing orbs float through the desert night.

The summer home of the largest colony of bats in the world.

A collection of vintage liaison aircraft kept in flying condition and on display at an airfield in San Antonio.

A 2,500-pound wooden nickel makes this woodworking museum easy to spot from the road.

In the hometown of the Grand Ole Opry star is a larger-than-life memorial statue made entirely from chicken wire.

This tiny 19th-century tunnel was built so a man could move his cows from one field to another.

Follow the steps, and this roadside artwork will teach you how to dance.

The world's largest collection of porcelain "veilleuses-theiere," or night light teapots, includes four that belonged to Napoleon.

The site of the one of the most deadly train wrecks in American history.

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

Over 20,000 sets of spice shakers reveal the surprisingly telling history of our most basic spices.

All you ever needed or wanted to know about America's favorite whiskey, but not a drop to drink.

Labor provided by Great Depression-era programs restored these 25,000 acres in Tennessee.

Visit this playground of waterfalls, caves and sinkholes.

Enormous lake at the bottom of a unique cave system.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

The secret city built by the Manhattan Project.

A curiosity-seeker's paradise set inside a three-story historic school house.