The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

Walk through spectacular aisles of hanging meat and wagon wheel–sized cheese at the world's largest wholesale food market.

The ruins of a Duke's bucolic dream, where camels once roamed alongside "Dutch" windmills and faux-Italian vineyards.

France's national museum of scientific and industrial instruments.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

Abandoned railway line circling the city of Paris.

France's most famous cemetery, with some of its most curious tombs.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

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

A crumbling hospital from the 1850s on Roosevelt Island.

One of only two commuter aerial tramways in the United States.

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

Concerts, art, offices, and a café in what used to be Berlin's first crematorium.

Berlin's beloved bear is immortalized at the Museum für Naturkunde.

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

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

Tiny memorials honor individual victims of the Holocaust.

A traditional U-Bahn station in Berlin gets a string of rather untraditional benches.

Cold war icon and onetime "hole" in the iron curtain.

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

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

When German-Iraqi relations broke down, this embassy was vacated post haste.

From Iggy Pop to David Bowie to Nick Cave, this regal music studio has served some of the all time greats.