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

This city square is home to Amsterdam's oldest church and a statue honoring Dutch sex workers.

The history and future of cannabis.

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.

More than 200 statues filled with cryptic symbols give this park spot an aura of horror vacui fantasy.

Eat a meal surrounded by bomb fragments.

Believed to have once stored either human remains or rice wine, thousands of mysterious stone jars lie in ruin.

Budapest's Communist-era statues, banished to the suburbs.

Nikola Tesla's ashes are held in a golden sphere, surrounded by his works.

A marvel of Byzantine engineering under the streets of Istanbul.

An underground city of salt.

Ottoman-era houses lovingly preserved.

Romania's triumphal arch looks out over Bucharest.

When you've got to go, you've got to go.

340-foot statue built to honour the Heroes of the Soviet Union.

The deepest metro station in the world.

This "tower of death" has acted as an observatory, a religious hub, and an executioner's lair.

A forgotten remnant of the Soviet Union, Transnistria is an unrecognized country hidden behind a heavily militarized border between Moldova and Ukraine.

A gigantic collection of teeny, tiny books.

Mysterious hillside with a continuously burning natural fire.

A shrine of fire worship built on top of a natural flame.

18m long sarcophagus of a constantly growing dead prophet.

This cavernous swimming spot doubles as a home to the largest known colony of bats in Central Asia.