This ancient Roman bridge and aqueduct still stands as a wonder of classical construction.

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

A book collector's dream, this Toronto bookstore has the world's first "Biblio-Mat," a random book vending machine.

An enormous, inside-out glass globe built in 1935.

Holy Grotto of Montserrat Monastery holds one of Europe's mysterious black Madonnas.

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

Japan and South Korea both lay claim to islands inhabited by one woman.

Numerical symbolism abound at East Asia's oldest observatory.

Originally used to sell brandy, the bull-shaped billboard became an iconic symbol of Spain.

A towering monument in Spain has proven to be more labor-intensive than initially planned.

This underground church is topped with a 500-foot cross that is seen by many as a beacon of fascist hubris.

Giant topiary dog once played a role in a terrorist bomb plot.

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

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.

The Cathedral of Salamanca has a number of unusual carvings but none so surprising as a modern astronaut.

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

The final resting place of the great navigator, or maybe his brother.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Elaborate tile work in this railway station tells the story of Portugal.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.