A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

The oldest stone house in Paris was built by its most famous alchemist.

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

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

Notorious artist squat renovated into legal studios.

This massive library holds what was once the largest book collection in the world.

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

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

From Tintin to the Smurfs, Europe's greatest graphic icons are celebrated in a grand Art Noveau gallery.

Theme park featuring miniature replicas of European monuments.

Medical history with an amazing, if frighting, collection of wax diseases on display.

Each time a baby is born in Ghent, these streetlights flash in silent celebration.

The Belgian library displays burned books that were salvaged from the fires of both world wars.

This whimsical statue dumps water on its head to symbolize knowledge flowing into his brain. Or maybe booze.

A huge old mansion full of thousands of toys, each there to be used and played with.

This statue dedicated to the story of a Flemish boy and his dog was relatively obscure in Belgium, but a cult sensation in Japan.

Inside this former medieval prison is a collection of objects designed to inflict unbelievable pain and suffering on the human body and mind.

Most prolific publishing house in the 1600s open to the public.

The patron of this extravagant Art Nouveau confection insisted that nothing less than a boat should project from its facade.

This small corner bar is home to a rare 1930s dance organ that still plays tunes for one Euro.

Nature is slowly overtaking this disused cemetery on the outskirts of Brussels.

The bronzed skull of a beheaded traitor was affixed to the city gate in the 17th century.