Go inside to really appreciate this 500-year-old technological masterpiece.

100 year tradition of fist fights, marked by marble footsteps.

This massive blockhead sculpture hides an entire library.

This cemetery features modernist statues as strange as its name.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

An ancient tower built during Roman times as a lookout post still stands to this day.

World's largest crossword puzzle spans the side of a towerblock, its clues scattered throughout the city.

This unique Lady Liberty is one of the only examples of the figure sitting down.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

An underground city of salt.

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

A whimsical bridge adorned with decorative dragons.

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

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

Baroque celebration of the end of the Great Plague of Vienna.

Op-art architecture designed for happiness.

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

Budapest's Communist-era statues, banished to the suburbs.

Museum dedicated to the terror regimes of Hungary.

A random tree outside a Budapest hotel has become a DIY shrine to the late singer.

A museum dedicated to a secret military hospital hidden beneath a castle in Budapest.

Uh, pardon me, ma'am, but I couldn't help noticing that there's a Columbo statue in the middle of Budapest.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.