A new hypothesis about the Great Pyramid of Giza in Egypt suggests the monument could be far older than the date accepted by mainstream Egyptology, according to a study by Italian engineer Alberto Donini of the University of Bologna.
The Great Pyramid, one of the ancient world's Seven Wonders, has long been dated to the reign of the pharaoh Khufu, an Egyptian ruler of the Old Kingdom's Fourth Dynasty whose rule is placed around 2560 BC. Donini's method, based on the erosion of the pyramid's limestone, produced results that push its possible construction much further back in time.
The research, published in January 2026 on the academic platform ResearchGate, examined twelve points at the base of the pyramid. Donini calls his approach the Relative Erosion Method, or REM. It compares surfaces that stayed protected by the pyramid's outer casing until medieval times with other surfaces that have been exposed since construction. The study has not yet gone through independent peer review.
What the erosion study found
Donini's method starts from the premise that part of the Great Pyramid's exterior casing disappeared over time, a process he says was accelerated by an earthquake in 1303. Some stones ended up buried under sand, preserving sections that, according to the researcher, could serve as a reference point for calculating how much material the structure lost through exposure to the elements.
Based on those differences, Donini's model produced exposure periods ranging from about 5,700 years to more than 54,000 years. The average placed construction of the pyramid around 22,941 BC, with the main statistical range falling between 8,954 BC and 36,878 BC. Donini estimated a 68.2% probability that the pyramid falls within that window.
The report also raises the possibility that Khufu restored a much older structure and later associated it with his own reign, rather than building the monument from scratch. Donini himself cautions that the REM does not produce an exact date, but rather a probabilistic window for how long the rock has been exposed.
Where the dating method runs into trouble
The model's main weakness lies in an assumption that is difficult to verify: that limestone erodes at a stable rate over thousands of years. Egypt went through major climate shifts, and during the African Humid Period rainfall was far heavier than it is today, a scenario that could have sped up the wearing of exposed surfaces.
Other factors also complicate the calculation, including wind, the periods when the pyramid's base lay covered by sand, the activity of microorganisms, and wear caused by tourism. The method also assumes that the compared surfaces started out with a similar composition and condition, something that has not been independently verified.
What the established evidence shows
The dating accepted by Egyptology places construction of the Great Pyramid at around 2560 BC, during Egypt's Fourth Dynasty. That conclusion does not rest on a single technique. Archaeologists link it to the development of Egyptian architecture, pottery found at Giza, and inscriptions from tombs and quarries connected to Khufu's reign.
Radiocarbon testing points to the same period. Researchers have used organic material associated with Egyptian monuments, including plant remains and charcoal found in mortar, to refine the chronology. These methods are less affected by climate variation than an erosion-based model.
For now, Donini's proposal opens a striking debate but does not displace the date supported by established archaeological evidence.
