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

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

A wall of chewing gum moonlights as collective art.

Possibly the most beautiful carillon in the world, set atop Iron Mountain in Florida.

This float factory takes the mask off of Mardi Gras and lets visitors see where the magic happens.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

A large circus museum with summer performances.

This museum remembers an apocalyptic cult that became more famous for baseball than religious radicalism.

A hot dog stand where the heads are just as hot as the dogs.

A science teacher's dream.

An eccentric park and pool.

This cheerfully-named branch of the Chicago River is the fetid result of years of blood, entrails, and meatpacking waste.

This popular pilgrimage site offers a hole filled with holy healing dirt.

Sweden's "good old days" painstakingly re-created in a model village.

It houses the remains of a 17th-century version of the Titanic.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

Miniature art that tells an enormous story.

See massive fossils that are over 200 million years old in northeastern Arizona.

A spiritual vortex among the red rocks in Sedona.

A multi-storied adobe complex has been inhabited for more than a thousand years.

A sprawling collection of over 106,000 toys from around the world.

A museum devoted entirely to the rattlesnakes and snake-related art.