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

A spectacular rainbow of stained glass makes the "Pink Mosque" one of the most beautiful in Iran.

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

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

A collection of iconic Soviet car models on display.

An enormous Soviet aircraft, the only one of its kind, stands at the deserted shore of the Caspian Sea.

A monument to the defenders of the Arctic in Murmansk, Russia.

Replica of mosque destroyed by Russia in the 16th century.

The coldest city in the world.

A small part of Russia that does not touch any other part of Russia.

Some of the world's only freshwater seals live in one very special lake in Russia.

The world's second-largest excavated hole.

The villagers of the coldest inhabited place on Earth adjust to unique challenges presented by day-to-day living.

A nightmare for the claustrophobic lies hidden in Southeast Asia.

The ruins of an ancient Zoroastrian Tower of Silence believed to be the earliest example of the traditional funerary practice.

One of the most ethnically diverse spots on the planet.

Former island in the Aral Sea used to be a top-secret Russian bio-weapons facility.

Ancient barriers wrap around what was once an important stop along the Silk Road.

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

This peaceful Sikh gurudwara serves around 50,000 free meals every day within its gilded walls.

Complete town of 5,000 living out at sea on the world's first offshore oil platform.

Home to nearly a third of the world's mud volcanoes, Azerbaijan is home to a messy, bubbling, and sometimes explosive landscape.

Swirling layers of white and red rock earned these mountains their festive nickname.

This striking icon of the disputed Republic of Artsakh caused a stir at a Eurovision Song Contest.