During the Egyptian Old Kingdom (2650-2135 BC), the most impressive of all monuments were built in the form of the pyramids and their associated temples. The provision of enormous quantities of stone from suitable quarries was the most important requirement for their construction. This volume comprises short archaeological descriptions of the pyramids and their enclosures and determines the exact origin of the building material (above all limestone) from a total of 26 pyramids through a petrographic and geochemical comparison with samples from other quarries.