This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.

3,000 market stands in five former Zeppelin hangars.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

A pair of connected skyscrapers form this symbolic gateway.

This massive subterranean fissure is known as the "underground Grand Canyon."

The yawning maw of this pagan visage is said to bite off the hands of liars.

The largest stone moai on Rapa Nui.

This was once the center of the Birdman cult, and is now a World Heritage Site.

The world's most remote airport.

This large round boulder is said to emit spiritual power, but it may just be magnets.

What started as a tongue-in-cheek shrine is now a full-blown museum celebrating "The Hoff" and his longtime love affair with Berlin.

Berlin's old airport.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

A program of Communist glamour in post-Stalin Poland is preserved in this colorful museum.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

A miniature train-ride through Slovenia's largest cave system.

This one-time health resort was used by aristocrats around the world.

Martin Bricelj Baraga's monolithic sculpture measures the blueness of the sky, and changes color to match it.

A whimsical bridge adorned with decorative dragons.

This abandoned Slovenian military barracks has become a punky-political art squat.

The charmingly disheveled clock tower of Tbilisi's puppet theater.

A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.