A man-made slag heap that you can "ski" down, and is home to the world sandboarding championships.

An ancient pagan site swirling with legends in the foothills of Franconian Switzerland.

These 18th century gardens tell a rocky story of the son of Odysseus.

When the rain falls, this drain system turns into a musical instrument.

Taste freshly foraged yarrow and black locust blossoms at this ambitious cocktail bar.

This conical hill was built as a testing ground for an engineer known as the Glider King.

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

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

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

These former Nazi anti-aircraft towers offer a singular view of the north of Berlin in the summer, and a sanctuary for bats in winter.

An eerie, derelict amusement park in Berlin.

This public observatory is home to the "celestial cannon," the longest pointable telescope in the world.

Floating swimming pool within a moored vessel.

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

Berliners converted a bombed-out, disused lot into a community-run urban farm with its own cafe and bar.

The last remnants of a massive medieval wall that once encompassed the city of Berlin.

What started as a tongue-in-cheek shrine is now a full-blown museum celebrating "The Hoff" and his longtime love affair with Berlin.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

A slice of central Asia in the middle of Berlin.

Reminders of the Battle of Berlin still scar the railway.

A haunting contrast of trains that both saved and took the lives of Jewish children in Nazi Germany.

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

Tiny memorials honor individual victims of the Holocaust.