The Great Pyramid of Khufu, the largest and most impressive surviving monument from the ancient world, has long remained an enigma to scholars. One reason is its remarkable resistance to damage from events such as earthquakes, which has helped it endure for thousands of years without significant structural issues.

Now, researchers say they finally understand the ancient technological factors behind the pyramid’s resilience throughout time.

According to new research, the unique frequency at which the pyramid vibrates during earthquakes contrasts significantly with the sands of the Giza plateau on which it rests. This, a new study in Scientific Reports argues, along with the massive structure’s shape and internal design, has all played a part in helping ensure its longevity.

A Marvel of the Ancient World

Khufu’s Pyramid, often simply called the Great Pyramid, is the oldest of the Seven Wonders of the Ancient World and the sole surviving example. Scholars have maintained a fascination with Giza’s monumental megastructures since antiquity, and debate over the mystery of its construction continues into the present day.

Completed during Egypt’s Old Kingdom (2600–2450 BCE), the Great Pyramid raises a significant question about the structural qualities that have contributed to its longevity. Addressing this aspect of one of the greatest engineering feats of the ancient world, researchers Mohamed ELGabry and colleagues Ayman Hamed, Sakuji Yoshimura, Hesham M. Hussein, Mohamed Maklad, and Asem Salama now say a combination of factors, which include the internal features within the pyramid, all contribute to its success at surviving events that have damaged smaller, more structurally sophisticated monuments in Egypt.

Using Sound to Solve an Ancient Mystery

To help them determine the factors that contribute the most significantly to the longevity of Khufu’s Pyramid, the research team began with an ambient noise survey, which involved horizontal-to-vertical spectral ratio analysis at more than three dozen locations throughout the ancient structure, which included chambers within the pyramid, construction blocks, and adjacent soil.

Their approach was not only successful but also revealed surprising insights into the pyramid’s construction, the team says.

Among the most significant discoveries, the team says they found that the pyramid “exhibits uniform fundamental frequencies (2.0–2.6 Hz) with an average of ~ 2.3 Hz across all structural elements,” revealing an extraordinary consistency in terms of the structure’s dynamic characteristics.

Also important, they say, is that the frequency band the pyramid’s structural components exhibit contrasts sharply with the surrounding soil. This is important because it limits the amplification of resonance through interactions between the stone assembly of the structure and its surrounding soil, which the team identifies as “a key mechanism protecting the monument during seismic activity.

Finally, although the team identifies an increase in seismic amplification with respect to the structure’s height, they also found that it “diminishes substantially within the pressure-relieving chambers,” which they interpret as an indication of “how their geometry actively reduces seismic response.”

Ancient Earthquake Impact Reduction

As a final consideration, the team also examined the pyramid’s subsurface foundation, where they calculated the structure’s vulnerability to seismic events.

After determining a very low value, the team concludes that the pyramid’s foundation has an “excellent bearing capacity and minimal earthquake-induced risk,” noting that, in addition to the monument’s resilience over time, its unique structural properties will likely protect it from future damage.

“The low seismic vulnerability index estimated for the foundation soils suggests that any future earthquakes are likely to produce only limited damage to the main pyramid body,” the team reports in their study.

Arguably, the team’s most significant finding is that the pyramid’s ancient builders possessed an exceptionally advanced understanding of the engineering properties behind the stone used in its construction.

“These findings present compelling quantitative evidence that ancient Egyptian architects possessed profound geotechnical understanding, optimizing structure design and site characterization to assure millennial-scale stability against seismic hazards,” the team reports.

The recent study, “Architectural and geotechnical aspects affecting earthquake resilience for the antique Egyptian Khufu pyramid,” appeared in Scientific Reports on May 21, 2026.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

Researchers have discovered new evidence that Neolithic people in the Judean Mountains achieved an engineering breakthrough 8000 years before the ancient Romans first used it.

The precocious ancient technology, now believed to have been invented nearly 10,000 years ago based on discoveries at the Motza archaeological site near the western edge of Jerusalem, involved burning local limestone and dolomite to create a form of plaster far stronger than other known varieties of the period, which mostly consisted of calcite.

Now, according to new research published in The Journal of Archaeological Science, long before the use of pottery, the ancient Neolithic inhabitants at Motza had discovered pyrogenic dolomite plaster and were using this surprisingly sophisticated engineering capability to craft plaster floors and other fixtures.

Pyrogenic Dolomite Plaster 8000 Years Before Rome

A primary ingredient of plaster is calcite, a whitish mineral composed of calcium carbonate derived from limestone.

However, during the Neolithic Period near modern-day Motza, early engineers had apparently already begun using not only limestone to make the plaster for their flooring but also dolomite found in the region. This is significant because the resulting pyrogenic dolomite plaster would inherit the properties of the dolomite stone, making it much harder and more water-resistant.

The earliest known written source that references such processes appears in the writings of the Roman architect and military engineer Vitruvius, who in the 1st century BC wrote of two rock types known for their use in making lime: a light-colored stone (limestone) and another hard stone, which most scholars believe to have been dolomite.

Given this reference, it was long believed that Roman engineers were the earliest to use dolomitic lime in such a manner, which is no simple task and demands a level of expertise at virtually every stage of its production that would have seemed inconceivable for ancient Neolithic builders.

That is, until now.

A Lost Technology Reemerges

Even in modern examples of dolomitic lime, as well as historical examples known to archaeologists, lime possessing magnesium generally isn’t recombined with the calcite-based lime to form dolomite—instead, known examples reveal that several different minerals rich in magnesium are formed, along with a range of other amorphous secondary compounds.

According to the recent study’s authors, “Surprisingly, the dolomitic plasters at Motza contain mainly dolomite and calcite, yet the properties of the dolomite support its identification as pyrogenic dolomite that re-formed after decarbonization in the plaster-making process.”

To determine whether the examples from Motza were indeed pyrogenic dolomite, the researchers conducted analytical tests on plaster kiln remains and floors at archaeological sites in the region. This, combined with studies of experimental recreations that mimic the suspected engineering of ancient the region’s Neolithic craftsmen and modern technologies such as scanning electron microscopy and light microscopy, led to an astounding discovery.

“The results suggest a technology lost to history that allowed a complete dolomite-lime cycle, similar to the known calcite-lime cycle,” the study’s authors report.

A New Understanding of Neolithic Engineering

According to the study’s authors, the ancient inhabitants of pre-pottery Neolithic Motza followed a traditional method for making plaster, though with one major difference: they adopted standard recipes that normally use lime or gypsum, and instead began using local materials available to them at the time.

Whether by accident or because of trial and error, Motza’s ancient residents managed to perfect the use of dolomite under such conditions “despite technical difficulties.”

As far as how this was specifically achieved, the researchers behind the new study suggest that “They may have successfully made dolomitic plaster where dolomite is fully recrystallized along with the calcite,” which they add is “something that to our knowledge has not been observed anywhere else.”

The recent study by Yonah Maor, Dmitry Yegorov, et al, titled “Neolithic plaster floors at Motza: Earliest case of burning dolomite for plaster,” appeared in the June 2026 issue of The Journal of Archaeological Science.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.