A 19th-century subterranean reservoir repurposed as a contemporary art cave.

In 1863, a woman buried her hard-drinking husband beneath his beloved booze.

The oceanic dumping ground where spaceships go to die.

This supper-club-turned-concert-venue still serves drinks at its original rotating bar.

The wild west is still alive and well at this authentic mining town watering hole.

This mysterious artificial cave has long puzzled New Englanders.

A gorgeous gilded tower houses what may be the world's largest collection of gin.

Blue-green pools and smooth stones comprise one of Spain’s most idyllic hidden wonders.

Was this cave created by Hercules's wrath, the devil, or volcanic activity?

Don't get it twisted: This is the oldest pretzel bakery in the United States.

An eatery in a shallow river where diners can enjoy their meal mere feet from the base of an artificial waterfall.

A small house sits between two huge rocks, with its back to the sea.

This Central New York ghost town was once a prosperous railroad community.

Water of undetermined depth has attracted rare fish and cult leaders alike.

In the foothills of the lesser Caucasus, a centuries-old fortress still stands.

With a crest near 10,000 feet, this treeless fault-block mountain in eastern Oregon provides stunning views and spectacular glacial landforms.

The longest navigable underground river in the United States is home to countless blind and albino animals.

The largest outdoor art gallery in the Northwest United States.

Tucked away in the forests of Indiana resides an abandoned waterslide that is now a popular graffiti haunt.

A fire lookout atop a glacial pinnacle is reached by climbing three vertiginous flights of stairs.

Once thought to be the oldest living tree in the world, Methuselah was germinated before the Egyptian pyramids were built.

Only intact Ichthyosaur skeleton in the United States.

Ruins of the elaborate house where the enigmatic costume designer threw glamorous parties for New York's theatrical elite.

A fire station-turned-church-turned-museum dedicated to the work of seminal light artist Dan Flavin.