Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

Ancient serpentine sacrifice holder that has stood the test of time.

Standing proud atop a Turkish bluff, this Ottoman palace has retained its grandeur despite being abandoned for centuries.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

A marvel of Byzantine engineering under the streets of Istanbul.

The hallucinogenic center of the ancient world.

Monasteries on rock pillars, once accessible only by frayed ropes.

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

This small shrine is dedicated to the designer of the first Russian fighter jet and his brother, who became Chairman of the Presidium of the Supreme Soviet.

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.

A geological oddity topped with a 2,000-year-old pagan temple.

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

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

A dreamy mausoleum honors Persia's most famous poet.

These little castles each held thousands of pigeons.

17th century mosque for Shah Abbas' harem.

The ancient necropolis houses the immense rock-cut tombs of four Persian kings.

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

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

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

This local emblem is the oldest and largest dragon tree in the Canary Islands.