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

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

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.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Golden cobblestones remember a time when this small alley was used to avoid having to give a Nazi salute.

These bronze pamphlets remember a remarkable group of Germans who fearlessly opposed the Nazis in the very center of their power.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

Sail in for a ’dam good slice.

Three connected pink triangles memorialize persecuted gays and lesbians throughout history.

This basement museum explores the art and artistry of fascism.

The history and future of cannabis.

A floating cat sanctuary on an Amsterdam canal.

Museum preserving torture methods from the past.

Dr Barnes' $25 billion private collection of art and arboretum.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

World's first "penitentiary," meant to be humane, drove men insane.

Rusting away on the edge of New Jersey are the remains of a Cold War missile launch site.

A very classy 1920s-era bar right in Grand Central Station.

This subterranean oyster house has been the pearl of Grand Central Station since 1913.

Home to items never before seen by the public.

An iconic location along the Los Angeles River where countless movie scenes are filmed.

This Hollywood dive houses a mural painted by the artists who animated its namesake film.