A pair of connected skyscrapers form this symbolic gateway.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

A beautiful mountaintop mausoleum devoted to a Montenegrin icon can't seem to make everyone happy.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

Explore the complex ecology of this multifaceted nature preserve by riverboat.

It's always summer at the beach inside this former airship hangar.

This giant, 83-year-old ship elevator is an engineering feat to behold.

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

Germany's Glienicke Bridge has a shady history of clandestine meetings, espionage, and spycraft.

This Berlin island is home to a flock of free-roaming peacocks, as well as a historic ivory folly.

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

Gardens representing parts of Asia, Europe, and the Mid East are tucked away among the Soviet-style buildings in East Berlin.

Started as a kitchen garden, now the second largest botanical garden in the world.

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

An eerie, derelict amusement park in Berlin.

Metro station with a claim to rock n' roll fame.

Berlin's old airport.

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

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

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

This World War II bunker now survives as a documentation of the Nazi regime and war crimes.

Berlin's natural history museum houses the world's largest mounted dinosaur and the late beloved polar bear Knut.

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

Tiny memorials honor individual victims of the Holocaust.