From remain observations of different pyramids can be deduced that Egyptians were very skilled in walls erection. One can thus observe structures with degrees like the pyramid of Meidoum or that of Meritetis with inclined walls of approximately 70°. These observations lead us to think that Cheops pyramid was first constructed as a degrees pyramid before being transformed into a smooth-faced pyramid. In order to build the corresponding massives the stones would have been lifted along slightly inclined walls that could reach 8.9 to 17.8m high (lifted and not pulled along ramps as it is more efficient to lift than pull). The volume of these stones representing more than 84% of the pyramid volume if we take into account massives deduced from Flinders Petrie measurement.