Mysterious lost empire of the Silk Road.

Only a handful of these gorgeous historic waterwheels remain but even those are in danger from local unrest.

This ornate mosque is said to hold the remains of Muhammad's granddaughter beneath its dome of pure gold.

Ruins of the Crusaders' headquarters.

Named after a legendary garden called Eram in southern Arabia, built by order of Shaddad, an Arab king who wanted to compete with Paradise.

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

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

Azerbaijani ghost town, decaying after a war left it an armed forces buffer zone.

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

Guests become prisoners on a visit to Latvian prison.

Khmer Rouge's high security prison.

This Armenian monastery was carved out of cliffs and named after the spear used to stab Jesus.

The most visited pilgrimage site in Armenia once held a saint in a pit for 13 years.

Rusting ships sit in a desert where a sea used to be.

Once a bustling fishing port, this semi-ghost town is now more than 90 miles away from the shore.

Japanese national treasure originally built in 593 CE.

A plaque marks the site directly below the mid-air detonation of the atomic bomb over Hiroshima.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.

This attraction was abandoned after the Chernobyl disaster.

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

12th-century holy complex shares land with a natural park full of heavenly waterfalls and raptors.

The deserted remains of a luxury hotel turned hospital ward.

An abused and forgotten metropolis, abandoned for centuries.

Roman ruins top white travertine terraces formed by ancient hot springs.