Once visited only by the cognoscenti of the ancient world, over the last decade Petra has drawn almost a million visitors in some years. Petra burst into popular consciousness with the release of enormously popular motion picture Raiders of the Lost Ark in 1981. Moviegoers all over the world were introduced to some of the spectacular scenic wonders of Petra: the Siq, a narrow chasm with colorful, towering sandstone walls, and Al-Khazna,...