An architectural oddity hides in plain sight on this iconic London bridge.

Hear the quietest sound from across the dome.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

The original home of the Lego has a huge amusement park dedicated to the iconic plastic toy.

Walk inside a half mile long crevice right outside the town of Garmisch Partenkirchen.

The small alleys in Lübeck's Old Town are a result of medieval urban sprawl.

This contentious squat has stood through fire, violence, and government intervention as a hotbed of leftist protest.

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

Model Trains and Much More in Hamburg.

This museum tells the story of lake dwellers from 4000 BC to 850 BC, replete with stilt houses and goats.

Dress up like a miner and take a slide into the disco-lit depths of this once foundational salt mine.

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

A Black Forest cuckoo clock theme park features one timepiece big enough to walk inside.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

A long spiraling walkway winds through the woods, and around a copper beech tree at the center.

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

This historic stone bridge has an entire neighborhood clinging to its sides.

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

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

This outdoor library provides around-the-clock access to around 7,000 books.