A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

Elevated freight railway turned wildly successful urban park.

Try not to get slimed in Tribeca.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

A crumbling hospital from the 1850s on Roosevelt Island.

An old department store turned Nazi prison turned artist commune.

The music is over at the Ballhaus Riviera Ballroom, but the ballroom remains in haunting disrepair.

A museum dedicated to a Cold War era sausage.

Come stay at a live-in art installation.

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

A towering monument to war, located on a beautifully peaceful hill.

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.

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

A brush maker used his factory to protect blind Jews from the Gestapo.

Berlin's old airport.

A fascinating insight into daily life in the Eastern Bloc.

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

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

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

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

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

The most visited, and possibly most controversial, museum in Germany.