The deepest metro station in the world.

This massive monument was unveiled the day Kosovo declared independence from Serbia.

This Slovak bridge is known both for its connection to a national uprising and its UFO-shaped eatery.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

This automated sculpture of two men peeing will spell out text messages with their micturition.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

A Jenga-style cylindrical tower of books that appears to go on forever.

A hidden three-foot-wide house separates these two regal churches.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

Elaborate tile work in this railway station tells the story of Portugal.

This statue of the great Argentinian car driver is located near a famous curve of the Monaco Grand Prix.

Sky ships, planes, and portraits left as unique tokens of hope and thankfulness.

A vast Communist-era exhibition space in the Bulgarian capital.

A striking symbol of the Bulgarian capital.

Bridge that died in war and was resurected.

Taking the subway here means doing so over a bridge located in the middle of an estuary.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

Stockholm's narrowest alley is barely over two feet wide.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

People in Poland have rallied to save this unnatural desert from being reclaimed by the forest.

This man-made mound monument was built out of soil from all across the Polish empire.