This iconic 1,000-year-old medieval castle is a favorite of the film industry, most notably as the location for Hogwarts in Harry Potter.

The sign at the garden gate reads: "These Plants Can Kill."

Traditional architecture and ancient irrigation systems are on display in this gorgeous mountain village.

This bazaar is one of the oldest in the Arabian world.

A sinkhole and now a swimming hole, too, full of dazzling turquoise water.

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

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

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

Traditional 11th-century outdoor tannery.

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

The largest madrasa in Morocco once housed more than 900 students within its exquisite walls.

The other side is actually green.

Mosaics, storks, and brothels—this ancient city has it all.

2300-year-old Roman road connecting the empire.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

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

This Welsh village gave itself a ridiculous name in a publicity stunt a century ahead of its time.

The lighthouse is on a island which is connected to another island, which is connected to another island, which is connected to one of the largest islands in the world.

A former fisherman's hut deemed too small for habitation is now a delightful tourist draw.

The largest 19th century panorama in the world still in-situ.

It appears as if a man is standing behind this giant airport clock, painting the hands in real time.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.

Birthplace of the "Cat in the Cradle" and a cluster of iconic, original windmills that let the Dutch tame the seas.

This futuristic building is yet another architectural wonder in Dubai.