By the dawn of the IIIrd Dynasty (circa 2700 BC), Egypt was sufficiently advanced and prosperous to support ever larger building projects. King Zoser, first monarch of the IIIrd Dynasty, decided to show off his wealth and success by constructing for himself the most imposing mastaba yet. He was fortunate to have as his architect Imhotep, one of the first identifiable geniuses of history. Imhotep designed an impressive mastaba for Zoser, but it wasn't grand enough for his royal master. While it was being enlarged, Imhotep had a design breakthrough: he decided to pile other, slightly smaller mastabas atop the original one. Moreover, Zoser's tomb would be wrought in stone, not mud brick. Zoser must have been delighted, for study of his tomb shows it was recast once more with six ascending levels instead of four. The result was the first pyramid in Egypt, known as the Step Pyramid. (The name is purely informational; Zoser's tomb resembles a set of steps.) In its final form the Step Pyramid dwarfed all previous royal tombs, as it was 140 meters long, 118 meters wide, and sixty meters high. An elaborate walled enclosure encompassed the pyramid and mortuary temple into a sacred precinct where Zoser could be revered for all time.
Is the pyramid shape significant, other than as the inspiration of architect Imhotep? Whatever their advances, the Egyptians were limited in what they could build, both by the materials they possessed and the technology they understood. They did not know how to build domes or arches, as the Greeks and Romans used later in their monuments. The pyramid is a simple geometric solid, the only shape other than rectangles the Egyptians could build with the materials and methods they knew.
On the other hand, the pyramid did acquire religious significance. The royal cult was closely linked to worship of the sun god Ra. A hieroglyph developed at the dawn of Egyptian history depicts the sun as a phoenix perched atop a pyramid-shaped object called a benben. This benben has been taken to represent the sun's rays spreading to the earth, so a definite symbolic link can be found between the solar cult and the tombs of the pharaohs, the sun god's son on earth.
...up next: Construction Methods - No, the pyramids were NOT built by extraterrestrials. Their builders left ample evidence of their terrestrial construction.
Secrets of the Pyramids - The First Pyramids - Construction Methods - Pyramids' Final Fates