The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

A fiery crater has been burning in the Karakum Desert since 1971.

An old vending machine serves up unpredictable beverages from its seemingly magical insides.

Since 1874, this macabre collection has developed into a museum devoted to Scotland Yard's mementos of dastardly deeds.

A one-of-a-kind collection of a unique medium.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

The rocks in this arid basin leave trails of movement behind them.

An eerie, derelict amusement park in Berlin.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

The fairy tale castle of the "fairy-tale king."

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

The neon signs from Las Vegas' past find their final resting place at this unusual graveyard.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

World's largest collection of serial killer artwork and other macabre exhibits.

World's first "penitentiary," meant to be humane, drove men insane.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

Non-profit time travel mart sells goods you would need for a trip through the fourth dimension.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

On Japan's Tashirojima Island, cats are king.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.