The Pyramids of Giza – built by the ancient Egyptians or not? 

It’s one of the most hotly contested debates in archaeology and history. From armchair conspiracy theorists to YouTubers, journalists, and scientists, countless studies, treatises, and polemics have been attempting to crack one of the most ancient mysteries of this Earth. 

Now, a team of Italian and Scottish scientists believes they may have deciphered it in a study that claims the pyramids sit on top of an “underground city” or the mythical Halls of Amenti beneath the Pyramids of Giza. Experts dismiss it as “fake news.”

Dubbed The Khafre Project, named after the middle and second-largest of the three pyramids, Corrado Malanga of Italy’s University of Pisa and Filippo Biondi of the University of Strathclyde in Scotland say they’ve discovered massive structures up to two kilometres beneath the surface of the 4,500-year-old wonder of the world.

Using a modified version of Synthetic Aperture Radar (SAR), a technique patented by Biondi, the team claims to have discovered an enormous limestone platform containing eight vertical shafts spiralling pathways downward, connecting to two cube-shaped structures each measuring 90 meters per side.

Electromagnetic signals were turned into phononic data that unveiled larger infrastructure leading down thousands of feet underground.

The team also says that they had identified a water system more than 640 metres below the pyramid, located beneath the platform, with underground pathways burrowing deeper into the earth. 

Malanga believes they have discovered “what can only be described as a true underground city.” Speaking at a news briefing in March, Malanga said this city can be viewed when the images are magnified. 

Folklore or more? 

This team joins a growing faction of archaeology and history enthusiasts who challenge the official accounts and narratives of how and when the pyramids were constructed. 

The bottom line of their argument is that the mysterious structures could not possibly have been built by the ancient Egyptians, as they did not possess the technology to accurately build three eight-sided pyramids, accurately aligning with true north. They argue that there is no conclusive evidence to prove that the pyramids were meant for and built by the Fourth Dynasty pharaohs of ancient Egypt.

This deviation from mainstream narrative” comes with various lore and legend. Some say the pyramids were ancient power stations. Others credit aliens. American psychic Edgar Cayce hyped the idea in the 20th century that a hidden “Hall of Records”, part of Halls of Amenti, lies beneath the Giza Plateau.

The Italian and Scottish scientists lean into that hypothesis, suggesting that “the Pyramid of Khafre might conceal undiscovered secrets, notably the fabled Hall of Records.” That’s the mythical, ancient library holding records of the fabled Atlantis that lay under the Great Sphinx, as Cayce claimed.

Such thinking goes against the canon and is promptly shot down by veteran Egyptologists like Zahi Hawass, Egypt's former Minister of Tourism and Antiquities.

“I'm telling you that this theory, as well as other theories, I say goes with the wind always because it has no scientific basis at all,” Hawass tells TRT World. 

“All the scientists that I contacted, they said there is no way that this technique can show 168 meters under the ground. This is number one,” Hawass says, continuing, “number two, the base of the Great Pyramid and the base of the Second Pyramid is completely made of solid rock, no stones, and there is nothing that can be under a solid rock at all.” 

 Science in question

The crux of the issue lies with the use of Synthetic Aperture Radar (SAR), a remote-sensing technology used by space agencies like NASA and the European Space Agency (ESA). NASA’s website defines it as thus: “an instrument sends out a pulse of energy and then records the amount of that energy reflected back after it interacts with Earth.”

When TRT World reached out to ESA asking about SAR’s ability to gauge potential underground structures beneath Giza Plateau, ESA responded that “the radars have a limited capacity to penetrate the soil. This capacity varies with the frequency used and can go up to 10 meters.” 

This is something Biondi concurs with: “I think that the 10 meters that the European Space Agency gave you is really optimistic, and in my personal opinion is absolutely less than 10 meters, because the power spectra density from space to the Earth is very low. And so, it's impossible.”

Technically, at this point, Hawass, the ESA and Biondi agree as to the SAR’s limited underground capacity. 

ESA adds that the “techniques allowing the measurement of structures located hundreds/ thousands of meters can only be indirect ones, requiring modelisation and interpretation.”                                                                                                

The researchers say they carried out their work by developing a new method for interpreting SAR signals by combining the Doppler effect with tomography. 

“We used a new technique. Why?” Biondi asks. “Because we observed very carefully how the Synthetic Aperture Radar images are synthesised.”

It gets technical here, Biondi explains the procedure: Step one is called “range compression,” where they use a reference signal (called a "chirp") and match it to the way the radar signal scatters over distances, providing a partially focused image in the range dimension.

Step two involves what's called the Doppler history, which results from the satellite's movement, travelling at around 7 kilometres per second. It allows the team to simulate a Doppler-based communication channel.

Through these techniques, the team was able to create a specialised processing "recipe." The usually impossible goal of looking kilometres underground was rendered potentially achievable by focusing on azimuth compression (the side-to-side dimension).

"We realised that azimuth compression is very similar to processing sound. And sound only travels through matter — not through empty space. The denser the material, the faster sound travels through it. That means in dense underground environments, we might be able to interpret radar signals similarly to how we process sound, which could improve the depth and clarity of our underground imaging," they tell TRT World. 

To help them amplify vibrations, the team “developed a software that is able to extrapolate the sound from Earth.” With that sound, they “evaluated a technique to perform acoustic tomography using radar.”

“A synthetic aperture radar that passes over the Earth at that velocity is like a giant microphone that listens to the Earth's tiny movements due to vibrations. We record these movements and we perform the so-called tomographic inversion,” Dr Biondi explains.

“We try to have a carton wrapped and we unwrap this carton and we have the picture of the scans inside the Earth.”

Scepticism over interpretation

Other criticisms of the research say that the scientists employed artistic liberties when interpreting their data. When asked, teammate Armando Mei, who is a researcher in Egyptology, told TRT World:

“First of all, over the past year, we have analysed more than 200 tomographies and satellite data provided by two American aerospace companies, Amberspace and Capella Space, which made open-source data available to the entire scientific community. And we detected the underground of Giza with different satellites, not one satellite, but different satellites, positioned at different points of observation.

“The results are always consistent. That’s why we’re confident. The study of tomography has revealed a clear and homogeneous distribution of the wells.”

The latest study on the structures underneath the pyramids utilise the same methods documented in an earlier peer-reviewed study published in 2022 employing SAR Doppler Tomography to look into the internal structure of the Great Pyramid of Giza.

Biondi employed his method in its early stages to gauge the structure of the Mosul Dam and the Grand Saso Laboratory, in what he said was to evaluate “vibrations of large infrastructures, like huge bridges, or also huge man-made objects.”

Yet, for Hawass, the researchers’ work contradicts established principles on the pyramids. 

“How can they ignore all the archaeological evidence, the Wadi al-Jarf papyri, the discovery of the tombs of the pyramid builders, and they try to announce and use the pyramid to be famous?” he asks. He refused to engage further with the research.

The scientists declined to respond specifically to Hawass’s allegations, saying that they wish to distance themselves from polemics and would like to “remain fully open to a constructive and respectful conversation with Dr. Hawass at any time, place, or setting of his choosing.” 

For now, they say they will “continue the satellite scanning of the Giza Plateau until its completion, as planned.”