In 1986/87, under the aegis of the Fondation EDF, almost one thousand microgravimetrical measurements were taken. They revealed a particular anomaly about the density of the pyramid

This model fits nicely with the previous image

The density anomaly observed is lacking any basic symmetry other than a certain spiral appearance, EDF notes in its analysis report

Jean-Pierre Houdin's 3D internal ramp model shows amazing similarities with the previous image

Note the notch on the edge at right

Details on a notch on one edge of the pyramid

Jean-Pierre Houdin's model superimposed on a real notch. This could be the upper part of the ninth recess of the internal ramp

Clearly visible lines on the face of the Great Pyramid could be an indication of the presence of the internal ramp

Upper part of the Great Gallery today

Showing the V-shaped upper end required for passing ropes through, according to Jean-Pierre Houdin's theory

Lower portion of the Great Gallery. Note the holes dug into the stone at regular intervals in opposing positions on the side banks

Perfectly surfaced and jointed limestone at the base of the pyramid

4,500 year-old ropes made of vegetal fibers

The Egyptians, who were great seamen, were masters of this technique

The 4,500 year old solar boat shows how the Egyptians mastered wood and rope work

Showing carpentry expertise

The same technologies mastered are likely to have been used in the construction of the pyramid.