Archaeologists Discover Mysterious Underground 'Anomaly' Near Giza Pyramids

Archaeologists have discovered a mysterious underground "anomaly" at the site of an ancient Egyptian cemetery within the iconic Giza pyramid complex.

The subterranean anomaly was observed with the help of surveys involving a pair of geophysical techniques—ground-penetrating radar (GPR) and electrical resistivity tomography (ERT). These methods enable archaeologists to detect possible structures lying beneath the surface, which can then be excavated.

The surveys have resulted in some "quite important" findings that point to the possible presence of archaeological remains that were previously unknown, a study published in the journal Archaeological Prospection has reported.

The latest study was conducted by a joint research team involving experts with Higashi Nippon International University and Tohoku University in Japan, as well as the National Research Institute of Astronomy and Geophysics (NRIAG) in Egypt.

The GPR and ERT surveys focused on the Western Cemetery in Giza, which was an important burial place for ancient Egyptian royalty and high-class officers. This cemetery, to the west of the Great Pyramid, is densely populated with "mastabas"—a type of ancient Egyptian underground grave.

"A mastaba is a type of tomb, which has a flat-roof and rectangular structure on the ground surface, constructed out of limestone or mudbricks," the study authors wrote. "It has a vertical shaft connected to a subsurface chamber."

"Most such sites are buried under sand, and it is not easy to locate their exact positions from the surface. Under such conditions, their positions can be identified by the geophysical exploration methods."

While the Western Cemetery is filled with mastabas, there is a flat, vacant area—without any above-ground structures—where no excavations have been carried out to date. It is this area that the team explored with their surveys.

The team's investigations revealed a significant subsurface "anomaly" in the data that they believe corresponds to a combination of a shallow structure connected to a deeper structure.

The shallow structure, which lies at a depth of up to 6.5 feet, is L-shaped and measures around 33 feet by 49 feet. This may have served as some form of entrance to the deeper structure, according to the study.

"It seems to have been filled with sand, which means it was backfilled after it was constructed," the authors said.

The deeper structure, which lies at a depth of about 16 feet to 33 feet, extends over an area of around 33 feet by 33 feet.

While it is not clear exactly what lies below the surface at this location, the anomaly could correspond to a grave-related structure.

"We believe that the continuity of the shallow structure and the deep large structure is important. From the survey results, we cannot determine the material causing the anomaly, but it may be a large subsurface archaeological structure," the authors said.

"It is important that [the remains] must be promptly excavated to establish their purpose."

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