The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

Hitler's bleak vision of relaxation still stands as a mostly abandoned 10,000-room resort complex.

Twisted buildings adorn the banks of the Rhine river.

This former steel and coal plant is now a neon-lit industrial fantasia.

The "Prussian Versailles" that is as glorious today as when it was built.

The walls of Germany's Parliament still show the scars of the Red Army takeover in World War II.

No need to strap in for a “ride” on this walkable roller coaster.

A 12th-century fortress containing some of Berlin's oldest buildings.

This "floating railway" is one of the world's oldest monorail systems.

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

A fascinating insight into daily life in the Eastern Bloc.

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

An Art Nouveau building covered in animal gargoyles and grotesques.

The deepest metro station in the world.

One of the largest museums in Ukraine remembers the story of the German-Soviet War in iconic, brutalist style.

340-foot statue built to honour the Heroes of the Soviet Union.

This unassuming museum's slogan translates to “there is a limit of sadness, anxiety has no limits."

Reputedly based on the tomb of Jesus Christ, this crypt is the oldest surviving structure of any cathedral in England.

Locals affectionately dubbed this World War I memorial "Tommy."

A museum and gardens with unusual plants and a history of progressive programming for the blind.

England's largest white horse isn't even white.

These remarkable cascades are the jewels of Upper Tees.

These planks were originally installed to hold the dead.

The dance of this huge clock is a magnificent and eerie commentary on good and evil in the history of humankind.