The earliest known map to show America, discovered by accident at a Paris bookshop.

This small museum tucked within a subway station holds pieces from Madrid's past.

For decades, Puerta del Sol has been illuminated by a giant, guitar-wielding bottle of sherry.

A whimsical brother of the nearby Fallen Angel statue takes the falling part quite literally.

A rare set of strings by famed instrument maker Antonio Stradivarius is on display in the Royal Palace.

Strange masks and obscure costumes are housed in this old Madrid corrala.

Abandoned tunnels dug for the once-thriving sea salt industry on the coast of southern Spain.

This 7,000-year-old megalithic wonder covered by a Franco-era reservoir emerges in times of drought.

This ancient Visigothic church might hide an ancient treasure.

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

A small town celebrates its cash crop with a giant highway sculpture.

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

Single runway interrupted by a busy road that cuts across its middle.

The Roman city was the birthplace of various emperors and is home to one of the empire's most impressive architectural feats.

London's smallest police station is barely the size of a phone booth.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

This 19th-century fountain's namesake animal isn't what you think it is.

Long tunnels run under the ancient chariot racing circuit to the tower.

Stained glass windows bathe this botanical garden in cosmic light.

It's believed this golden brick is part of the legendary lost Aztec treasure.

Come face to face with the ferocious visage of the serpent-headed mother goddess of the Aztecs.

The turquoise-studded skull of a long-dead Aztec man sits within Mexico City’s Museum of Anthropology.

This colossal ancient jaguar sculpture was used as a vessel for the hearts torn from sacrificial victims.

Many people don't realize there’s a lot going on in—and below—the world’s tallest triumphal arch.