A musical instrument played by the sea.

This sprawling concrete suburb of Kraków was designed by the Soviet Union as the model proletarian city.

An underground city of salt.

The former Nazi Germany concentration camp stands as a museum to remember this dark chapter in European history.

A rare example of a medieval house in Rome adorned with a melancholic inscription.

This small, ancient Roman temple was once a church dedicated to the patron saint of penitents.

This curious, round temple is the oldest still-standing marble building in Rome.

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

The first museum in the world devoted to sexual gadgetry.

A plaque marks the spot where the saint was shoved off the Charles Bridge and into the river.

An eerie, existential museum dedicated to the author of "The Metamorphosis."

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

An Orwellian sculpture with eyeball cameras watches passersby.

Walk through Czech history in Prague's largest graveyard.

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

Looming communist pillar with a Czech twist.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

The holes in this wall provide a glimpse into Jewish life in Budapest, both past and present.

This quiet, unassuming spot in Budapest was the birthplace of the bloody 1956 Hungarian Revolution.

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 diminutive statue that was inspired by the sculptor's own daughter.

The true meaning behind this sculpture remains unknown.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.