A mocking tribute to the past and modern leadership of Prague.

This oddly beautiful water cistern is a techno-temple to the wet stuff and a multimedia masterpiece.

A mysterious concrete hand reaches out from between the stones of Uniwersytecki bridge.

A collection of old neon signs from all over Poland line a secluded courtyard.

Relive a Polish uprising via an enormous, century-old cyclorama.

A striking public sculpture representing the period of martial law in Communist Poland.

A 90-ton, gravity-defiant steam locomotive shoots for the skies in this bizarrely beautiful public artwork.

The silly symbol for an underground protest group is now scattered around the city.

This ex-prison dates back to the Middle Ages.

In the center of Wrocław's old meat market stands a somber tribute to the city's livestock.

When the public was consulted about a new piece of street art, they naturally asked for an enormous metal dragon.

A labyrinthine underworld of tunnels and caverns hides beneath the city.

An oddity of a bygone era that stills functions today.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

Named for a doctor who made a breakthrough in London’s cholera epidemic, this 1800s pub was also the site of a queer “kiss-in.”

This 19th-century pub features stained-glass windows celebrating Victorian-era “champions.”

This third-generation institution is one of the last in London that still cures its own salt beef for epic sandwiches.

This London marker celebrates the spot where the world-famous English band was founded.

A plaque marks the underground site of one of London's "lost rivers."

An eccentric Victorian aristocrat's enormous collection of medieval armor and weapons from around the world.

A commemorative plaque at the door pays tribute to an "American Patriot" known for his betrayal.

This tribute to the fictional detective stands at the famous literary character's address.

Hidden beneath the streets of London is a secret subway that only carried mail.

One of the most studied Iron Age settlements in Europe.