Sun temples of the Fifth Dynasty are an unparalleled monument of ancient Egypt, characterized the Central part of the Old Kingdom considered as the apex of the solar cult and theology.Original architectural shape and ideological influence on the later phases of Egyptian history are far from clear as well as their cultic, ideological and symbolic relationship with the contemporary pyramids and with what is considered to be the original place of rise and diffusion of the solar cult in AE, the city of Heliopolis. Six temples were built in a quite limited time span in the middle of the Third Millennium BC but only two have been discovered so far. The volume collects all the available archaeological and textual evidences, including an in-depth reconstruction of the original decoration of temples.