Residents of Berlin take their coffee and cake in one of the city’s most restful spaces: a cemetery.

The non-native bovine herd was brought in to help conserve these Berlin wetlands.

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

The final resting place of many of Germany's most famous communists.

One of downtown Berlin's last reminders of its Communist past.

Named after a militant urban guerilla, this famous former squat is a graffiti-covered stronghold of leftist culture.

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

Blitzkrieg bop your way through Berlin's Ramones Museum.

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."

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

An eerie, derelict amusement park in Berlin.

This mural painted by Keith Haring was done without payment as a gift to entertain the children at the Hôpital Necker.

This recessed garden protects thousands of mountain plants by creating its own microclimates.

A mud statue stands in the dark tunnels, seeming to hold up the weight of the city above.

This frog-themed restaurant was frequented by Picasso, Saint-Exupéry, and more.

The industrial architecture honors the laborers who brought the Exposition Universelle of 1900 to life.

Beggars were miraculously "cured" of their fake ailments when they returned home to this 17th century Paris slum each night.

The narrowest street in Paris.

This banal Parisian entranceway is not what it seems.

This old cement mine has been used as everything from a mushroom farm to a recording studio.

The curious underground history of keeping Paris clean.

A grotto-like lodge decorated with gilded mosaics, rocks and a noisy waterfall was the setting for the most sumptuous pleasure house of 1900s Europe.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.