Within sight of the Egyptian megapolis, Cairo, rises the Giza Plateau with its world famous complex of monuments, including the Cheops, Kephren and Mykerions pyramids, long thought to have been tombs of the pharaos whose names they bear. When Upper and Lower Egypt were united as one kingdom in 2900 BC, the capitol was located near Memphis. The age of the pyramids began during the Old Kingdom. It culminated in the Cheops or Great Pyramid of Giza. The suburbs of Cairo have since expanded almost up to its base.