An incarceration museum on the spot of possibly the oldest prison in England.

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

Eighty million natural history specimens call this gargantuan museum home.

The quaint little store that is said to have inspired a famous Dickens novel was only given its name after the book was released.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

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

A kaleidoscopic warehouse-maze of handmade neon signs.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

You can crawl inside this atmospheric 5,000-year-old tomb.

The former home of a mad diplomat is said to still be marked in bloody, arcane scrawls.

A public urinal so pretty, it was declared a national monument.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

Museum preserving torture methods from the past.

These bronze pamphlets remember a remarkable group of Germans who fearlessly opposed the Nazis in the very center of their power.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

A stairway to heaven, or to nowhere at all.

The prototype for all Nazi concentration camps.

A museum dedicated to a Cold War era sausage.

Reminders of the Battle of Berlin still scar the railway.

These former Nazi anti-aircraft towers offer a singular view of the north of Berlin in the summer, and a sanctuary for bats in winter.

This conical hill was built as a testing ground for an engineer known as the Glider King.

A restaurant and observation deck built in a unique broadcasting antenna.