Rusting railcars and locomotive equipment fill this Ethiopian train graveyard.

An Ethiopian "Jerusalem" featuring a church hewn out of a single rock.

Supposedly this Ethiopian chapel holds the Ark of the Covenant, guarded by virgins who cannot leave the building.

Massive stele returned to Ethiopia after 70 years in Rome.

The best-preserved Roman small town in North Africa.

Founded in 670, this ancient mosque is an architectural time portal.

A 15th-century granary that played the role of futuristic slave quarters in the world of 'Star Wars.'

Ancient Manuscripts showcase the civilization of West Africans during the Middle Ages.

These homes carved into the mountains seem to defy the laws of nature.

The central mosque of this Mali town is entirely built from mud.

A more chill but no less fascinating version of the famous ancient archeological site.

The world's oldest map of the holy land gives us a fragmented glimpse of the layout of biblical nations.

Gladiators battle and chariots race daily in the ruins of a once-great Roman city.

An ancient capital city that dates back 3,000 years old and harbors many surprises.

The small cliffside monastery known as the Tiger's Nest is said to be the meditation site of an eighth-century Buddhist master.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

Op-art architecture designed for happiness.

The Habsburgs' royal collections of art and wonders.

Home of the future Emperors of Russia.

Stalinist skyscraper built with help of cryotechnology.

World's largest bell sits on the grounds of the Kremlin in Moscow.

This building holds the embalmed remains of the leader of the Bolshevik Revolution.

The only museum with its curator—and her pets—buried inside.

The small peaceful island off the Venice tourist circuit is where the city began more than 1,500 years ago.