Burial site of a Jewish prophet revered in Iran.

This beautiful system of tunnels built into natural rock serves as a centuries old plumbing system.

This ancient burial site is believed to be one of the first earthquake-protected structures in the world.

Mirrors and glass shards cover every inch of this arrestingly beautiful mosque.

This 12,000 year old Iranian cave village has been continuously inhabited for over 3,000 years.

The palace of the King of Kings, burned by Alexander the Great.

Marked by the hand of the explorer Henry Morton Stanley.

17th century mosque for Shah Abbas' harem.

These little castles each held thousands of pigeons.

Putrefaction plateaus in Iran, where the dead were sent for decontamination before going to their final resting place.

Go inside to really appreciate this 500-year-old technological masterpiece.

Over 50 exquisite hand-painted Renaissance maps decorate a Medici storage room.

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

Cliffside houses provide a spectacular view from their perch above the valley.

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

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

Holy Hindu shrine in an enormous, monkey-filled limestone cavern.

Hindu temple of the dead home to hundreds of long-tailed macaques.

Cat art as far as the eye can see.

The curious underground history of keeping Paris clean.

A nuclear power plant abandoned along with an international allegience.

What was once a unique system of urban elevators is turning into a mechanical ruin.

This historic, palatial theater is now one of the world’s most beautiful bookstores.

Buenos Aires' city of the dead contains some very famous remains, including Eva Perón.