This ex-prison dates back to the Middle Ages.

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

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

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

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

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

A monument to the man who almost killed Hitler.

The world's first clock to use set theory as a measure of time required the invention of a new light bulb just to maintain its obtuse measurements.

An astonishingly accurate water clock that doubles as an hourly spectacle in this Berlin shopping area.

A memorial in the Tiergarten is a reminder of the suffering inflicted on homosexuals by the Nazi regime.

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

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

This former floral display recalls Andover’s crucial role in Viking history in England.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

This once-controversial and slightly confusing statue of Achilles was built out of captured cannons.

Once designed as the entrance to Buckingham Palace, this structure was later relocated and stands as a victory arch.

The bar where "The Great Train Robbery" was planned was once a nexus of high society and low morals.

This striking statue brings a scene from the African savannah into central London.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

Once a 19th-century refuge for immigrants, this pub has hosted performances by Amy Winehouse and the Arctic Monkeys.

A miniature model of the iconic Stockholm department store.

A concrete mushroom that divided Stockholm residents for nearly a century.

Several cannonballs of mysterious origins decorate two buildings in Stortoget's main square.

There's something in the air as history repeats itself at this museum dedicated to the Swedish pop band.