Learn ten amazing facts about Petra, Jordan. Inhabited by Nabataeans over 2500 years ago, the city was carved into the walls of a desert canyon. The Treasury, its most famous structure, is estimated to be 2000 years old. Nabataeans prospered by controlling water supply in region. They used mechanisms like dams to store and sell water from flash floods. Spice trade further fueled Petra's prosperity in the first century BC.