This large round boulder is said to emit spiritual power, but it may just be magnets.

A volcanic crater that visitors can look inside.

In the Middle Ages, villagers would sound this stone trumpet to boost fertility and coax fish to shore.

The world's most remote airport.

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

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

A must for film lovers in Madrid and home to the Spanish Film Library's projection space.

An ancient Egyptian temple in the middle of Madrid, Spain.

Among the oldest structures in Madrid, these Moorish walls once guarded the medieval city of Mayrit.

A vault of safe-deposit boxes in an old bank has been repurposed as a time capsule of Hispanic culture.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

A pair of gigantic baby heads greet passengers at Atocha Station.

The remains of the second-oldest zoo in Europe can be seen within these library gardens.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

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

If you visit Santa's village, you can get your passport stamped to show you crossed into the Arctic Circle.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

This floating sculpture of ice is a poignant reminder of nature's power.

Housing the famous Norwegian ice-defying 19th century polar exploration ship.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

Roughly 17 million letters to Santa have found their way to this Arctic Circle post office.

A subterranean house of worship carved right out of the bedrock.

Rent out a glass igloo to watch the Northern Lights like you live in the future.

A Jenga-style cylindrical tower of books that appears to go on forever.