Once home to one of the oldest banks in the world, this building is also where Marco Polo's famous travelogue was written.

This peculiar Italian elevator runs both horizontally and vertically.

This cathedral hides a sculpted dog that determines your fate and an unexploded shell from World War II.

Claude Monet immortalized this medieval bridge in two of his paintings.

Only a few pieces remain of the structure that carried people and goods across the Thames for some 600 years.

Catacombs turned marketplace.

London's largest outsider art museum.

This ancient theater was once the home of fierce gladiatorial battles.

This salt marsh in Southern France is as pink as the flamingos that inhabit it.

This modern museum of Mediterranean culture is surrounded by a surreal concrete honeycomb.

This Parisian gem is one of the most incredible ethnographic museums in the world.

This Paris art space celebrates the creativity and ingenuity that springs from abject poverty, especially in Africa.

A series of abstract, silly sculptures represent the works of a great modern classical composer.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

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.

Notorious artist squat renovated into legal studios.

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

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

This deconsecrated church has seen many uses, from a tobacco storehouse to a cinema.

Go inside to really appreciate this 500-year-old technological masterpiece.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

See what remains of a once grand ancient Roman circus.