Great Pyramid of Giza may have been built over course of 20 years, using multiple ramps

Roig’s model found that using a single ramp would have been insufficient and would have required nearly half a century of construction to reach the pyramid’s completion.

The Great Pyramid of Giza may have been constructed using a helical, wrap-around ramp built directly into the face of the pyramid, according to a new study published in npj Heritage Science .

The study, conducted by independent researcher Vicente Luis Rosell Roig, presents the results of a mathematical simulation testing whether his theory, based on what he calls the Integrated Edge-Ramp (IER) model, actually works.

Rather than using an external ramp, which would have required enormous quantities of material and leave behind obvious archaeological remains, Roig claims that the ramp was built into the face of the pyramid, and later filled back in once it was completed.

Built around 2,560 BCE as the tomb of the Egyptian Pharaoh Khufu, the Great Pyramid is made from approximately 2.3 million blocks of limestone and granite. As it would have needed to be finished within the 27 years of Khufu's reign, a block would have needed to be placed at an average rate of one every three minutes.

Roig’s model found that using a single ramp would have been insufficient and would have required nearly half a century of construction to reach the pyramid’s completion.

However, using his proposed system, which would begin with up to 16 ramps and eventually scale down to a single ramp as the pyramid narrowed, could complete the job in as little as 13.67 years.

Factoring in quarrying, river transport, and seasonal pauses, Roig calculated the total duration of the project to be between 20 to 27 years, which would align with historical record.

The ramp itself, the study explained, would have been approximately 3.8 meters wide: enough to allow for two-way traffic, with loaded sledges carrying stone blocks up and empty sledges making their way back down.

One of the challenges Roig noticed was turning corners.

In the study, Roig estimated that 90-degree turns added roughly three minutes of delay each. To solve this, he suggested "corner platforms," built along the exterior of the pyramid that would allow teams to carefully manoeuver around the sharp bends.

The study also used finite-element analysis (FEA), a technique borrowed from structural engineering that divides a complex shape into thousands of smaller elements to simulate how stress is distributed, to confirm that temporarily removing blocks from the face of the pyramid would not compromise its structural integrity.

According to the results, after removing the edge blocks, stress levels in the pyramid remained well within the proposed “safe” limits.

Model appears to align with previous findings

Interestingly, Roig’s IER model appears to align geometrically with several features discovered inside the pyramid by the ScanPyramids mission, which is led by Cairo University and the French Heritage Innovation Preservation Institute (HIP).

Using muon tomography, the mission identified a large unexplained void and several smaller unexplained cavities and notches within the pyramid in 2016 and 2017.

The IER model's predicted ramp path, angled at a slope of approximately 7.4 to 7.5 degrees, would correspond with where the voids are located.

Even so, the study noted that the IER theory is "hypothesis-generating rather than confirmatory," adding that current scanning technology cannot distinguish a back-filled ramp from other types of void.