This subterranean disco dance club in a Cuban cave comes with bright lights and a dark legend.

The thousands of shades on display — some toxic, others impossibly rare — are a library of more than just color.

One man's swirling six-acre monument of stone.

A submerged archeological park still holds the wonders of a Roman Sodom.

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

The haunting ruins of a military fortress turned astronomical observatory sit on a Sarajevo mountaintop.

This impressive collection of rare books on ancient mysticism inspired author Dan Brown.

The oldest hotel in the world has been operated by the same family for over 1,300 years, even catering to samurai.

Palace where the nearly un-killable Rasputin was murdered.

This sword isn't waiting for a king to pull it out. It was placed there by a saint.

One of the world's oldest and most massive living organisms is a grove of quaking aspens.

A solitary tree has grown up all alone on Lake Wānaka, backdropped by the beautiful Southern Alps.

A swing to dangle you off the very edge.

Staves, storm-calling, and of course, necropants.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

On the Oregon coast there is a natural hole that seems to be draining the sea.

Brightly colored 30-foot-tall totems light up the desert sky just outside Las Vegas.

An Australian lake whose pink hue defies scientific explanation.

This former coal gasification plant found a curious second life as a popular public park.

Beijing's expansive subterranean hiding spot now crumbles away as a tourist destination.

Slaughterhouse Five opens its dank doors to fans of Kurt Vonnegut.

Super-heavy Nazi architectural experiment.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

An eerie, derelict amusement park in Berlin.