Modern-day cave dwellers carve elaborate homes out of volcanic debris.

This circular Iranian jail was once a political prison run by the country's secret police.

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

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.

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

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

Marked by the hand of the explorer Henry Morton Stanley.

Cockatoo Island is a Heritage-listed island in the middle of Sydney Harbour.

A collaboration of art and ornithology mourns the calls of Sydney's lost birds.

A special train service transported Sydney's dead from this station to "Necropolis Receiving Houses" at Rookwood Cemetery.

Ninety years of Sydney buses under one roof.

An otherworldly restaurant perched on the edge of a jagged cliff next to a medieval holy city.

An imperial fortress city that incorporated cultural elements from the entire Mughal empire, only to be abandoned the year it was finished.

Home of the unusual art of water puppetry, one of Vietnam's oldest curiosities.

Sacred Buddhist home of some spiritual monkeys.

The most famous location in China was home to whole dynasties worth of imperial rulers.

Beijing's version of Disneyland, completely abandoned, mostly destroyed.

Named after the Goddess of Harvests, Annapurna is the deadliest member of the Eight-thousanders club.

The world's longest outdoor covered escalator system transports commuters through Hong Kong's hilly terrain.

A small subculture of boat dwellers keep their traditional way of living alive at this Hong Kong Typhoon Shelter.

Teeming with illegal goods and services, this towering maze of vice is also a popular tourist accommodation.

Ha Long Bay's "Cave of Surprises" houses a popular phallic rock formation.