Step inside the first house designed by Catalan architect Antoni Gaudí, considered to be one of the first Art Nouveau buildings.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

A beautiful but toxic fountain of mercury.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

The world’s tallest outdoor lift stretches along the stone pillars that inspired the floating mountains in the movie “Avatar.”

An immersive projection art installation uses sound, scale, and light to take visitors inside classic works of art.

The industrial architecture honors the laborers who brought the Exposition Universelle of 1900 to life.

Former hunting lodge of a duke who was an avid collector of impressionist works.

This banal Parisian entranceway is not what it seems.

One of the last umbrella repair shops in Paris upholds the nostalgic art of umbrella making.

Where the high court feasted, frolicked, and high courtesans put their royal lovers' diamonds to the test.

Hidden away in a modern library are the remains of one of the 18th century's most celebrated wunderkammers.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.

The curious underground history of keeping Paris clean.

Paris' fabled purveyor of exotic taxidermy and natural history curios.

A majestic lion statue guards this Parisian botanical garden, and feeds on an unsettling item.

The history of radiation is on safe display at the foot of a radiation science laboratory.

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

Egyptian Revival movie palace abandoned for decades and restored in 2013.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

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

France's national museum of scientific and industrial instruments.

A mechanized clock where a man fights off a dragon, crab, and rooster.