 Today, only the four retaining walls remain standing, including the Western Wall.These walls created a flat platform (the Temple Mount) upon which the Temple was then constructed.Herod's other achievements include the development of water supplies for Jerusalem, building fortresses such as Masada and Herodium, and founding new cities such as Caesarea Maritima and the enclosures of Cave of the Patriarchs and Mamre in Hebron.