New discoveries about Egypt’s great pyramids seem to occur on an almost weekly basis, with many mysteries still waiting to be uncovered.
For instance, what was sealed in the Great Pyramid of Giza 4,500 years ago? How were the materials transported to the area before construction?
Even then, something seemingly as simple as “How many sides does the Great Pyramid have?” does not give the answer you would expect.
The answer is not four.
Modern society did not confirm this correct number until the Royal Air Force pilot P. Groves photographed the pyramid from above in 1926.
From that vantage point, one can see that the sides of the pyramid are significantly independent along their middle.
“The Great Pyramid at Giza is known to have an amazing character of concavity that each of its four faces is slightly indented along its central line, from base to peak,” explained Akio Kato from the Department of Mathematics and Physics at Kanagawa University, Japan, in a 2023 paper.
“In other words, the Great Pyramid is a concave octagonal pyramid rather than the standard square pyramid. This concavity is [too] subtle to be seen from any ground position, but can be observed from the air.”
These indents are believed to add stability and longevity to the pyramids.
“The inclined layers together with the reinforced base were necessary for the long-term stability of the Pyramid against the severe natural forces like the high gravitational compression, earthquakes and rainstorms, pointing out the feasible fact that the Pyramid has experienced severe rainstorms more than 500 times during the 4,500 years,” Kato wrote.
“The crucial point about stability is that the effects of such natural forces are quite different between the core of inclined courses and that of truly level courses in the sense that the former can be tightened to become stronger over time, but the latter would be disintegrated to be weaker over time.”
The fact that the pyramids remain standing today is a testament to how good Ancient Egyptian engineers were.
However, the design is not faultless.
Several sealed corridors and rooms within the structure may have been abandoned by builders when they were found to be unstable, raising questions about whether this was an intentional design choice or one that simply materialised.
