This surreal statue brings a famous French novel about a supernatural cad to arresting life.

Montmartre's sole surviving windmill became an iconic landmark for 19th-century painters, artists, and bohemians.

A giant silver apple a day keeps the perils of capitalism away.

A lone cannonball remains lodged in the walls of the Hotel de Sens as a sober reminder of a revolution.

This modest marker near Notre Dame identifies the very center of Paris.

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

The location of this small park was once the site of an infamous public morgue.

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

The narrowest street in Paris.

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

This 400-year-old tree is actually an immigrant from North America.

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

The remains of the medieval wall that once surrounded Paris with ties to the construction of the Louvre.

Remains of Roman amphitheater hidden in a sleepy quarter of Paris.

This colorful statue welcomes visitors to a Barcelona park.

One of Antoni Gaudí’s earliest buildings, built between 1886 and 1890 for the industrialist Eusebi Güell.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

An open-air "garden" of mural art that changes weekly.

A beautiful but toxic fountain of mercury.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

This bustling Italian plaza is built on the ruins of an ancient Roman amphitheater.

Fortified medieval tower house with lovely roof garden.

A dismembered holy head stares out from her beautiful reliquary at the St. Dominic Basilica.