PETRA JORDAN
When the Nabataeans were defeated by the Romans in 106 AD, Petra became part of the Roman province of Arabia, but increasingly the trade routes continued to decline as trade routes changed. After the city was damaged by an earthquake in 551, housing appears to have closed significantly. The city remained unknown to the Western world after the Crusades until Johann Ludwig Barkardt, a Swiss traveler, discovered it in 1812.
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