The Sed festival (ḥb-sd, conventional pronunciation ; also known as Heb Sed or Feast of the Tail) was an ancient Egyptian ceremony that celebrated the continued rule of a pharaoh. The name is taken from the name of an Egyptian wolf god, one of whose names was Wepwawet or Sed. The less-formal feast name, the Feast of the Tail, is derived from the name of the animal's tail that typically was attached to the back of the pharaoh's garment in the early periods of Egyptian history. This tail might have been the vestige of a previous ceremonial robe made out of a complete animal skin. The ancient festival might, perhaps, have been instituted to replace a ritual of murdering a pharaoh who was unable to continue to rule effectively because of age or condition. Eventually, Sed festivals were jubilees celebrated after a ruler had held the throne for thirty years and then every three to four years after that. They primarily were held to rejuvenate the pharaoh's strength and stamina while still sitting on the throne, celebrating the continued success of the pharaoh. Sed festivals implied elaborate temple rituals and included processions, offerings, and such acts of religious devotion as the ceremonial raising of a djed, the base or sacrum of a bovine spine, a phallic symbol representing the strength, "potency and duration of the pharaoh's rule". Festivals throughout history Despite the antiquity of the Sed festival and the hundreds of references to it throughout the history of ancient Egypt, the most detailed records of the ceremonies—apart from the reign of Amenhotep III—come mostly from "relief cycles of the Fifth Dynasty king Neuserra... in his sun temple at Abu Ghurab, of Akhenaten at East Karnak, and the relief cycles of the Twenty-second Dynasty king Osorkon II... at Bubastis." There is clear evidence for early pharaohs celebrating the Heb Sed, such as the First Dynasty pharaoh Den and the Third Dynasty pharaoh Djoser. In the Pyramid of Djoser, there are two boundary stones in his Heb Sed court, which is within his pyramid complex. He also is shown performing the Heb Sed in a false doorway inside his pyramid. One of the earliest Sed festivals for which there is substantial evidence is that of the Sixth Dynasty pharaoh Pepi I Meryre in the South Saqqara Stone Annal document. The most lavish, judging by surviving inscriptions, were those of Amenhotep III (c.