A new study published in Archaeological Prospection revealed that archaeologists have found a strange underground chasm near the Great Pyramid of Giza, also known as Khufu’s pyramid.

According to the research team, archaeologists had been using ground-penetrating radar and electrical resistivity tomography to see if they could find anything underground — and they did.

What they found was a shallow L-shaped structure that seemed to be full of sand and it connected to a deeper underground chasm. The team believes these chasms were filled up after being built, but it is possible that the deeper chasm could be a void.

Thus, there’s a chance that this anomaly is a “large subsurface archaeological structure,” per the study.

Where was it found and why is it significant?

According to Newsweek, the underground anomalies were found in what’s known as the Western Cemetery, next to the Great Pyramid of Giza. This cemetery was used for Egyptian royals and often contained underground graves known as mastabas.

The Great Pyramid of Giza is over 4,000 years old, according to Smithsonian Magazine, and many of the mastabas around it belonged to the pharaoh’s family and high-rank officials. The study explains mastabas as “a type of tomb, which has a flat-roof and rectangular structure on the ground surface, constructed out of limestone or mud bricks.

“It has a vertical shaft connected to a subsurface chamber. Most such sites are buried under overburden sand, and it is not easy to locate their exact positions from the surface.”

While most of the cemetery have above-ground structures, there was a section that was bare. According to Live Science, this is where the archaeologists used the ground-penetrating radar and electrical resistivity tomography to determine if there was anything hidden underneath the sand.

In an email to Live Science, one of the authors of the study, Motoyuki Sato, said, “Excavations to determine what the L-shaped structure is are now underway,” with him believing that there is no way this could be a natural feature due to the shape being too sharp.

Egyptologist Peter Der Manuelian from Harvard University also told Live Science that “it’s an interesting area, one that has avoided exploration due to the absence of superstructures.”

According to the study, many excavations of the mastabas occurred in the 20th century, dating back to 1929.

How ground-penetrating radar is changing archaeology

Never-before-seen archaeological discoveries have abounded since ground-penetrating radar entered the archaeological field. Now, archaeologists have been able to find more underground without needing to dig.

Earlier this year, researchers were able to find an ancient Viking marketplace underneath a Norwegian island, per Smithsonian Magazine.

In Turkey last year, archaeologists found remains of a multistory structure underneath the Roman Zerzevan Castle, per NPR.

In 2020, archaeologists used this technology to find the remains of an ancient Roman city, per Reuters.

Australians are currently using ground-penetrating radar to find missing or unknown graves as part of the Missing Children Project, according to The Guardian. Back in September 2023, they were believed to have found several unknown graves at the “former government-run Kinchela Aboriginal Boys’ Training Home.”

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