In a paper recently published by the American Schools of Oriental Research, University of Alabama at Birmingham archaeologist Sarah Parcak, Ph.D., and Christopher Tuttle, executive director of the Council of American Overseas Research Centers, announced the discovery of a massive, previously unknown structure in Petra, a 2,500-year-old Nabataean city in southern Jordan. 

The city of Petra is one of the most famous archaeological sites in the world, located in Jordan’s southwestern desert. Petra is half-built, half-carved into rock, and is surrounded by mountains riddled with passages and gorges. The site was unknown to the western world until 1812. In 1985 it was designated as a United Nations Educational, Scientific and Cultural Organization World Heritage site and named one of the New Seven Wonders of the World in 2007.

Several scenes from the Hollywood blockbuster "Indiana Jones and the Last Crusade" were filmed in the ancient city. Parcak is often called a real-life, modern-day Indiana Jones for her leading work in space archaeology, using satellite images to identify sites for excavation.    

Tuttle and Parcak used Google Earth, high-resolution satellite imagery, aerial drone photography and ground surveys to locate and document the structure they describe as "hiding in plain sight." The project marks the first time this combination of methodologies has been used at the Petra Archaeological Park.

"Petra has been very well-surveyed over the years, so when the large rectangular form appeared on the satellite imagery, not that far south from the main city, I initially dismissed it," Parcak said. "It’s essential when you use any kind of remote sensing tools to go out on the ground and confirm what you think is there. Ground-truthing done by Chris' team revealed foundations, stairs and column bases. The team also used drones that captured stunning high-resolution images of multiple structures."

Tuttle led four ground-truthing trips to investigate four locations of interest identified by Parcak's analysis of satellite data. The newly discovered platform is roughly the length of an Olympic-size swimming pool and twice as wide. It is located about half a mile south of the center of the ancient city. Given its size, shape and prominent location, Parcak believes the site was a public structure and possibly had some sort of ceremonial function.

"We know that it isn’t just one large structure," Parcak said. "There are other smaller structures inside of it. So clearly a lot of effort was put into building it. What’s really fascinating is that there is nothing else like it at Petra. We are very excited about what it could be."

In the paper, Parcak and Tuttle note there are directly visible relationships between the platform and three structures east, northwest and north of the city. The similar architectural and construction styles and the pottery scatters along the surface of the site suggest the platform was built when Petra was flourishing as the capital of the Nabataean kingdom, possibly as early as the mid-century BCE.

Parcak is an associate professor of anthropology in the UAB College of Arts and Sciences Department of Anthropology. She is also a National Geographic Fellow and winner of the 2016 TED Prize.