Saqqara is the location of the burial grounds used by the ancient residents of Memphis. The name of this place may be derived from the god of funerals, Sokar. The most visible of structures located at Saqqara is the Step pyramid of Djoser. The pyramid of Unas is historically important because it is the first to have Pyramid texts inscribed on the walls of the funerary chamber. Saqqara is also the location of many Old and New Kingdom pyramids. Many of the private Old Kingdome tombs are famous for the beautiful scenes on their walls. Underground galleries that were used for the burial of sacred animals including baboons, ibises, hawks, jackals, dogs, cats, and bulls are located at Saqqara. The Serapeum is one of the most famous of the galleries and was used for the burial of the Apis bulls. Also Abwab el-Qotat, or “the Doors of the Cats” contains hundreds of cat mummies.