On this seven-year journey, I simply walk into the next story.

Paul Salopek, a National Geographic fellow, wanders through the ancient Nabataean ruins of Madain Salih, carved into sandstone outcrops some 2,000 years ago. These structures were used as tombs for the wealthy during the Nabataean era. The kingdom stretched from its capital Petra in Jordan south to Madain Salih in the Hejaz region of present-day Saudi Arabia.