DAVID’S JERUSALEM. The inhabitants of ancient Jerusalem built a massive tower (bottom right of above drawing) to protect the Gihon Spring. Located just outside the city’s walls, the spring was accessed via a fortified stepped passageway that led down to the cave on the eastern slope of the ridge where the waters emanated. This reconstruction envisions Jerusalem in the tenth century BCE during the time of King David, before the city had expanded north to include the Temple to Yahweh built by King Solomon. The Spring Tower, together with the Fortified Passage, may be the “Millo” mentioned in the Bible.