They used Petra as a trading hub because it was in a perfect spot along the trade routes for incense. Even though Petra is in a dry, rocky area, the Nabataeans were very smart and figured out how to live and even thrive there by using clever engineering and advanced ways to save water. Today, Petra is one of the best-preserved ancient cities in the world. It’s like stepping back in time! You can see houses carved into the mountains and walk along paths made from natural gullies and canyons.