One of the largest ochre quarries in the world, hidden in a limestone landscape.

This ancient theater was once the home of fierce gladiatorial battles.

Even France's favorite aquatic son Jacques Cousteau, couldn't get to the bottom of it.

A mechanized clock where a man fights off a dragon, crab, and rooster.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

An elevator into the Baltic Sea.

Hitler's bleak vision of relaxation still stands as a mostly abandoned 10,000-room resort complex.

A long spiraling walkway winds through the woods, and around a copper beech tree at the center.

This historic Art Nouveau townhouse was the former home of the son of a famous chemical inventor and industrialist.

This non-profit theatre in the heart of Brussels is dedicated to hosting independent films.

A fantastical 13th-century fortification sandwiched by a modern hotel in central Brussels.

This modern arts center is built around a gem of late-Baroque architecture.

A little sculpture with a large wardrobe.

Meet the bronze beloved pet to a family of famous peeing statues.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

Climb inside an iron crystal magnified 165 billion times its normal size.

Often mistaken as a medieval Gothic monument, this unique cornerstone only dates back to the 1980s.

The site is dedicated to an investigative journalist whose murder triggered a political uproar that changed Slovakia forever.

According to the local legend, these boys and ducks were turned to stone by an angered water goblin.

An ode to a soldier who came to town, fell in love, then began making his own sparkling wine.

A massive sculpture of an obscure Celtic coin that has become a symbol in Slovakia.

No one knows the origin of this creepy little stone man with an oversized phallus.

Launched by Napoleon's soldiers more than 200 years ago, a cannonball remains embedded in the tower wall.

The inverted pyramid design of this station stands out amid Bratislava's urban landscape.