Hundreds of thousands of concrete bunkers crowd Albania long after the fall of Communism.

A naturally beautiful, seemingly bottomless deep blue spring.

A medieval bridge stretches over a sulfur-rich river that leads to year-round natural hot springs.

The Vatican's secret porn-festooned bathroom was painted in erotic murals by one of the greatest artists of the Renaissance.

If you want to talk to the Pope you will have to stare down this surreal vision of Jesus rising from a nuclear hell.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

These giant volcano sponges in Antarctica are thought to be the world's oldest living animal, at 15,000 years old.

One of only two civilian settlements in the desolate lands of chilly Antarctica.

Southern Ocean waters and glacial forces transform the Antarctic ice into these stunning bridges and caves.

The best place to send your postcards home from Antarctica.

Naked scientists race around the pole in the frigid cold to try to join Antarctica's exclusive 300 Club.

The world's largest neutrino telescope searches for secrets of the universe at the South Pole.

An abandoned whaling station on an active volcano offers hot springs in Antarctica, surrounded by ruined giants of industry.

Natural time capsule containing an alien ecosystem.

The cathedral stands in New Jufa, Isfahan's Armenian quarter that was established in 1606.

This 17th-century structure is a beautiful testimony to traditional Persian architecture

The colorful soil of Iran’s "Rainbow Island" attracts artists and nature lovers.

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

Burial site of a Jewish prophet revered in Iran.

Salt cured mummies continue to turn up in this Iranian mine.

A historic trade hub teeming with gorgeous architecture, colorful goods, and vibrant designs.

A dreamy mausoleum honors Persia's most famous poet.

One of the largest and oldest caravansaries in Persia.

These little castles each held thousands of pigeons.