An ancient Roman theatre restored to its former glory in the Spanish city of Cartegena.

Bacteria and algae give the salty water its bubblegum hue.

This 47-story "M" needed 20 years to be completed

A gravity-defying "devil's bridge" that has a surprising architectural feature for its stability.

Geological storytelling.

This awesome Spanish castle is so fantastical it was actually used on Game of Thrones.

A site where “the ravages of the war are more striking…than any other place in contemporary Spain.”

Of the many chalices in the running for the Holy Grail, this one in Valencia Cathedral sure looks the part.

Vibrant street art created with mixed media.

This massive fiberglass Gulliver turns every visitor into a Lilliputian.

A micro-communist utopia in Spain with no police, no mortgages and full employment.

Spain's stunning solar energy plant.

An eerie collection of the surviving structures from a past celebration of the future.

The world's largest wooden structure.

A 16th-century Andalusian palace.

Saint Joseph was said to heal the deaf and blind, but it was a much smaller miracle that got him canonized.

The oldest giants in Catalonia are now displayed in a 14th-century Gothic church.

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

A fascinating little museum all about the rich history of Peru’s famous plant.

Death rituals and sacrifice inside a Peruvian megalith.

A painting in the historic Cathedral Basilica depicts Jesus and his disciples dining on a traditional Peruvian menu.

Did Inca children also slide down these smooth rocky slopes above Cusco?

A sudden, striking cluster of hills south of Padua has been attracting visitors for centuries.

This unimaginably large pile of sand near Nazca is one of the tallest dunes in the world.