Stockholm's deepest subway station is also a stunning ecological wonder.

This device was crucial to the Industrial Revolution development of Leeds.

Artists have long been drawn to these atmospheric 12th-century ruins.

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

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

A Stockholm metro station is home to an escalator that is not only the longest in Sweden, but among the longest in the world.

Located in an old church, this brewery produces a different kind of holy water.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

This floating sculpture of ice is a poignant reminder of nature's power.

Tucked away near more famous landmarks lies a statue meant to symbolize the confluence and continuing development of human culture.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

A remarkable feat of Victorian engineering across the Firth of Forth.

A monument to the 70s rock icon stands on the road into this small Scottish town.

Looking strangely like Rome's Colosseum, this unfinished tower has dominated the skyline for over 100 years.

The ruins of this gorgeous clifftop castle look like something from a fantasy novel.

This pedestrian footbridge honors Pero Jones, an enslaved African who lived in Bristol.

A symbol for the opposition to nuclear power around the world.

This colorful artistic feature atop a Danish art gallery allows visitors to stroll through a rainbow.

The heart of Dutch football history.

Rotterdammers' dirty minds gave this Santa a dirty nickname and cursed it to a life of wandering.

This towering church is home to a world-famous organ and a treasure trove of medieval art.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

A multi-storied painting that depicts the area's rich and diverse maritime history.