This mesmerizing, colorful structure looks like a tent made from stained glass.

The statue of a legendary giant who carried Christ and shouldered the world's sins.

One of the most spectacular bridges in Spain spans a narrow chasm that divides the city of Ronda.

This fortress sits atop a centuries-old well system.

For centuries, Jeddah’s old town was a major trading port and a point of entry for Hajj pilgrims traveling by sea.

A small museum contains one of the largest collections of ethnic and traditional headgear in the world.

Rare karst landscape eroded from a flat seabed.

This tower has survived the times despite being composed of mud and camel hair.

A network of tunnels runs underneath the buildings of this ancient village.

This charming Latvian lane doubled as Baker Street on the Soviet Union’s version of Sherlock Holmes.

This abandoned, turn-of-the-century astronomy hub is now the subject of more photographs than it ever took.

The rocks around this mountain are filled with so many carvings that the area became known as the "open library."

A phenomenon that appears to make gravity work in reverse has been attributed to jinn, supernatural spirits from Arabian folklore.

Medical museum that houses most notably the taxidermied remains of Vladimir Demikhov's famous two-headed dog experiment.

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

It's believed human settlements from the Palaeolithic Age were established not far from this canyon.

Abandoned station along an ancient pilgrimage route.

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

In the middle of a barren desert, a massive, solitary rocky thumb juts out.

Moorish signal station on a stratgic rocky outcrop.

Lions carved into the rockface adorn these two tombs built into the mountains of Dadan.

The oldest housing complex in Riga is a mini timeline of architectural trends.

This art installation at an abandoned lipstick factory has distinct anti-capitalist vibes.

This giant volcanic crater holds its very own field of salt.