
According to Houdin, the Ancient Egyptians built the 480-foot-high Great Pyramid of Giza from the inside out, using a ramp that spiralled around the pyramid's interior, 30 to 45 feet inside its external surface.
Hawass tested the theory on the ground in the area of the Pyramids, along with a number of eminent archaeologists including the American Mark Lehner and the German Rainer Stadelman. They concluded that the Frenchman's theory was scientifically impossible."
For an excellent summary of Jean-Pierre Houdin's theory see Bob Brier's piece on the Archaeology Magazine website.
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