A temple to modernity, tucked away amid Barcelona's more well known museums.

18th century anatomical amphitheater of the Royal College of Surgery of Barcelona.

An early 20th-century bullring converted into a modern shopping center.

This ancient Spanish castle sits high upon a hilltop.

Giant eggs, walls of bread, and nightmare surreality mark the largest collection of works by Salvador Dalí.

Known as the "Dodo Manège," this carousel features a herd of animals that have disappeared—or may be gone soon.

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

This stunning French estate was so lavish that it landed its original owner in jail for the rest of his life.

An unusual sand beach in the middle of a forest.

This enormous "cloth of the conquest" depicts the Norman invasion of England in mind-blowing detail.

The birthplace of the ferocious William the Conqueror, this castle is awash in medieval history.

This medieval tower is all that remains of the castle where Joan of Arc was held before being burned at the stake.

Sacked by Vikings, blessed by William the Conqueror, dealt a fatal blow during the French Revolution—these ruins have seen it all.

Museum in a swimming pool where the water still flows.

Tables of secondhand books fill the inner courtyard of this 17th-century stock exchange.

A sublime medieval path adorns the marble floor of one of the most beautiful Gothic cathedrals in France.

An image of the legendary saint stands in the shadow of a cathedral she liberated.

A unique museum tells the story of the day-to-day life of World War I soldiers.

The castle was reconstructed to fit Kaiser Wilhelm II's romanticized vision of the Middle Ages.

French Time Capsule-19th Century home revealed to the public.

A Gothic cathedral created from volcanic rocks.

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

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

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