For hundreds of years, automatons moving to metallic music have been marking the passage of time.

Hundreds of hidden passageways weave through the old quarters of Lyon.

This derelict superstructure was a very important warning system for the Soviet military.

This attraction was abandoned after the Chernobyl disaster.

One of the most poignant ruins of the Chernobyl nuclear disaster, the local football team's stadium has been quickly reclaimed by nature.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

For patriotic Russians, this memorial honoring the Soviet soldiers who died liberating Berlin in 1945 is the most sacred location outside of Russia.

You've probably seen these distinctive orange-tiled columns on the big screen.

This monumental work of art symbolizes the coming together of a previously divided city.

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

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

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

Berlin's old airport.

Floating swimming pool within a moored vessel.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

An abandoned NSA listening post on Berlin's "Devil's Mountain."

Where once there was a train station bathroom, there is now this German burger joint.

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

A retro Yugoslav congress, cultural, and business hall built in the 1970s, with an iconic world clock.

This feat of Brutalist architecture is also known as the Three Sisters.

One of Belgrade's most beloved animals.

Different sections of the Zemun Fortress were built in the 14th and 15th century as a response to the advance of the Ottoman Empire.

Stone age urban planning.

This ice cream parlor serves scoops of flavors like rakia, medlar, and poppy seed.