A French artist's vague warning hangs over Belleville.

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

A fantastical 13th-century fortification sandwiched by a modern hotel in central Brussels.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

The courtyard of this small Marinid madrasa is a dazzling example of intricate Islamic architecture.

This former royal palace with gorgeous gardens became the first museum in Morocco.

Fortune tellers, snake charmers, poets, and storytellers all gather on this historic square in Morocco.

The oldest known university in the world is in Fez, Morocco.

Traditional 11th-century outdoor tannery.

Along the most northwestern point in Africa is an ancient cave surrounded by legends.

An awe-inspiring mosque in Morocco with one of the tallest minarets in the world.

Thousands of narrow alleyways in an ancient medieval city make up what's believed to be the world's largest car-free urban zone.

It took 40 years to build this Eden-like garden in Marrakech, later restored by Yves Saint-Laurent.

The other side is actually green.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

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

Commonly acknowledged as the only public monument to the Devil himself.

Montreal's giant farmer's market is a foodie's best friend, especially in the winter months.

A grand Gothic Revival basilica with stained glass depictions of Montreal's religious history has only one soul resting in its crypt.

This 1967 experiment in modular architecture was designed to be a new model for urban living.