Bacteria and algae give the salty water its bubblegum hue.

The narrowest street in Paris.

The first green space constructed on an elevated viaduct.

France's most famous cemetery, with some of its most curious tombs.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

This small window display is dedicated to the noble carrot.

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

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

This bike path was sunk below water level for maximum wonder.

This tri-part waterfall is a little bit of fairytale beauty in the heart of Luxembourg's Little Switzerland.

This Luxembourg cave is covered in cryptic looking marks left by mining activity.

This hotel was once home to a steamliner company and became the final rest stop for Europeans heading to the New World.

Elegant marble and old vaults fill this historic Dutch bank turned office space.

Rotterdammers' dirty minds gave this santa a dirty nickname and cursed it to a life of wandering.

A statue of the second-tallest Dutchman in history.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

Berlin's old airport.

A restaurant and observation deck built in a unique broadcasting antenna.

A tree-like building perches on its trunk in the Steglitz neighborhood of Berlin.

An abandoned NSA listening post on Berlin's "Devil's Mountain."

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

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

There must be a pun in this haystack somewhere...

Elevated freight railway turned wildly successful urban park.