The Great Pyramid of Giza was built with structural features that helped it withstand earthquakes for about 4,600 years, according to researchers who studied how the ancient monument responds to vibrations.
The study found the pyramid has a broad base, low centre of gravity, highly symmetrical shape and internal chambers that reduce vibration amplification. Scientists also said it was built on strong limestone bedrock, which added to its durability.
Researchers used seismometers at 37 locations in and around the pyramid to record ambient vibrations. They found the structure showed a remarkably stable response despite its size and complexity.
The findings, published on Thursday in the journal Scientific Reports, add to understanding of why the tomb of Pharaoh Khufu has survived so long. The pyramid originally stood about 480 feet, or 147 metres, tall and remains about 455 feet, or 138.5 metres, high after centuries of erosion and stone removal.
The four sides each measure about 755 feet, or 230 metres, at the base, and the monument covers about 13 acres, or 5.3 hectares. It was the world’s tallest structure for about 3,800 years.
Scientists said the pyramid’s internal design helps disperse seismic energy. They observed that while vibration amplification increased with height in general, it fell within five chambers above the King’s Chamber, suggesting those spaces help protect the burial room from excessive shaking.
“These elements together create a well-balanced, coherent structure,” said Mohamed ElGabry, a seismologist at the National Research Institute of Astronomy and Geophysics in Egypt and lead author of the study.
“Ancient Egyptian builders clearly possessed practical knowledge related to stability, foundation behavior, mass distribution and load transfer,” said Asem Salama, a seismologist at the same institute and senior author of the study.
Salama said he would not claim the pyramid was intentionally designed for earthquake resistance, but said the builders appear to have developed solutions that created exceptional long-term resilience. The researchers said this knowledge likely came through trial and error, as earlier flawed pyramids showed.
The study comes after earthquakes in the region in 1847 and 1992 caused major damage, including the destruction of thousands of buildings and the death of more than 560 people in the latter event. The Great Pyramid suffered scant damage.
The pyramid sits on the Giza Plateau outside Cairo alongside other pyramids and the Great Sphinx, a site that continues to draw large numbers of visitors. The new research adds a modern scientific explanation for one of the ancient world’s most famous surviving monuments.
