This artificial cave looks like something out of a fairytale.

Street artists transformed an abandoned air vent into the beloved Star Wars robot.

This spooky statue sits outside a famous Prague theater.

The tunnel's elegant proportions keep you snug with no claustrophobia freak-out.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

This 19th-century pub features stained-glass windows celebrating Victorian-era "champions."

The sumptuous ceiling was one of the last things Charles I saw before his execution.

This curious sculpture represents the perseverance needed to take to the skies.

Berlin's old airport.

A 12th-century fortress containing some of Berlin's oldest buildings.

In memory of The Blur Building, the temporary exhibition pavilion of vaporous nothingness.

The second-highest train station in Europe.

Constructed along the shores of Lake Zurich, this pavilion is a walk-through work of art.

One of the highest emergency huts in the world has been waiting almost a century to give imperiled climbers a place to lie down.

A Swiss amusement park entirely dedicated to the theory of ancient astronauts.

Vines grow up the metal bars in this public park created from an old machine factory.