The papyrus of Dama Heroub contains one of the oldest depictions of an ouroboros - a serpent eating it's own tail. It dates from the 21st dynasty in Egypt, making it more than 3000 years old.
Here it may represent the zodiac, the unending cycle of constellations through the night sky.
It should be noted, however, that symbols of the sun in Egypt are generally composed of a red-orange disk surrounded by the body of the snake with a uraeus - an upright cobra's head - at the bottom. It represents the god Mehen protecting the sun god through its hazardous nightly journey. The uraeus, however, does not bite its own tail.
Egyptian culture also contains what may be the world's oldest reference to an ouroboros. Inside the pyramid of Unas, it is written: "A serpent is entwined by a serpent...the male serpent is bitten by the female serpent, the female serpent is bitten by the male serpent, Heaven is enchanted, earth is enchanted, the male behind mankind is enchanted." There is, however, no illustration to go along with this text.
