Once the grandest synagogue in medieval Spain, it now stands as a memorial of the 15th-century Jewish exile.

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

Occupied for six centuries by Franciscan Order nuns, this monastery is an amazing ode to Catalán Gothic architecture.

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

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

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

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A Spanish town built into the cliffs.

The hidden ruins of an old hydroelectric plant reclaimed by nature.

One of the most spectacular bridges in Spain spans a narrow chasm that divides the city of Ronda.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

A naturally mummified 2,000-year-old man.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

The world's largest reflecting pool is just two centimeters deep.

An Orthodox church built by the Royal Family for the Russian community exiled to the French Riviera.

This massive blockhead sculpture hides an entire library.

This demon atop the Notre-Dame de Paris looks utterly bored.

A museum dedicated to one of Paris’s most famous residents, tucked into a corner of one of the city’s most famous squares.

During the summer months, giant teddy bears take over Paris near Les Gobelins metro station.

The video game-themed street art first popped up in the French city.

A mud statue stands in the dark tunnels, seeming to hold up the weight of the city above.

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

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.