The breathtaking city of Petra was a vibrant trading hub that vanished from most maps in the seventh century A.D. It lay beneath a thousand years of dust and debris when, in 1812, a Swiss scholar disguised as a Bedouin trader identified the ruins as the ancient Nabataean capital.
Spread throughout a series of remote desert canyons in southern Jordan, Petra arose more than 2,000 years ago at the crossroads of key caravan trade routes between Arabia, Syria, Palestine, and Egypt. The Nabataeans carved most of the sprawling city's buildings, including temples, tombs, and theaters, directly into the region's towering red sandstone cliffs. Here, a Bedouin walks his camel past Petra's most famous building, Al Khazneh, or the TreasuryNimrud in northern Iraq was once the capital of the Assyrian empire. Feared as bloodthirsty and vicious, the Assyrians arose around the 14th century B.C. and dominated the Middle East for a thousand years.
Nimrud and the Assyrian Empire declined rapidly around 612 B.C., after Nimrud's sister city, Nineveh, fell to the Babylonians.
The ancient city of Persepolis in modern-day Iran was one of four capitals of the sprawling Persian Empire. Built beginning around 520 B.C., the city was a showcase for the empire's staggering wealth, with grand architecture, extravagant works of silver and gold, and extensive relief sculptures such as this one portraying envoys with offerings for the king.
The height of Persian rule lasted from about 550 B.C. until 330 B.C., when Alexander the Great overthrew the ruling Archaemenid dynasty and burned Persepolis to the ground.
More than 600 cliff dwellings made by the ancestral Pueblo people, also known as the Anasazi, are scattered throughout Mesa Verde National Park in Colorado (shown here).
The Anasazi arrived in the region as early as A.D. 550, building their homes and cultivating crops on the soaring mesa tops. Around 1150, though, they began to move their dwellings to the alcoves within the canyon walls. Most houses were quite small, but a few reached enormous proportions, housing up 250 people.