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

In this Parisian garden's grotesque former life as a zoo it fed exotic animals to the bourgeois and put humans on exhibit.

Two awe-inspiring globes from the reign of the Sun King hang from the ceiling of France's national library.

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.

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.

Barcelona's only remaining tram system takes riders to the Tibidabo funicular.

The former 1920s mansion of a prominent Catalan developer was used as the Soviet Embassy during the Spanish Civil War, and there is still a bunker below the garden.

A former steam-powered mill from the 1800s is now an industrial park with a giant steel dragon slide.

The largest Art Nouveau complex in the world is a Barcelona hospital with a 600-year-long history.

An unusual stroll through gentlemen's erotica demonstrates that pornography is timeless.

The oldest giants in Catalonia are now displayed in a 14th-century Gothic church.

This semi-secret storybook hedge maze is also the oldest garden in the city.

The rocks are a time capsule of a 407-million-year-old Earth.