The royal capital of Egypt during the Old Kingdom was Memphis. During the Old Kingdom era the great pyramids were built to be burial tombs for the Pharaohs. Because Pharaohs were believed to be given authority from heaven, they wished to walk to Ra, their Sun-god, after death. King Zoser's adviser Inhotep designed the pyramid, hoping to easily reach Ra. The tombs were built on the west bank of the Nile where the sun seemed to set. For this reason, the Old Kingdom is sometimes called "The Age of the Pyramids."