[A]archaeologists are discovering that ancient Petra was a sprawling city of lush gardens and pleasant fountains, enormous temples and luxurious Roman-style villas. An ingenious water supply system allowed Petrans not just to drink and bathe, but to grow wheat, cultivate fruit, make wine and stroll in the shade of tall trees... And scholars now know that Petra thrived for nearly 1,000 years... Constructed during the first century B.C. and the first century A.D., it included a 600-seat theater, a triple colonnade, an enormous paved courtyard and vaulted rooms underneath. Artifacts found at the site -- from tiny Nabatean coins to...