But David conquered the city, his attack being spearheaded by Joab, who evidently gained entry into the city by means of “the water tunnel.” (2Sa 5:6-9; 1Ch 11:4-8) Scholars are not entirely certain of the meaning of the Hebrew term here rendered “water tunnel,” but generally accept this or similar terms (“water shaft,” RS, AT; “gutter,” JP) as the most likely meaning. The brief account does not state just how the city’s defenses were breached. Since the discovery of the tunnel and shaft leading to the Gihon spring, the popular view is that Joab led men up this vertical shaft, through the sloping tunnel and into the city in a surprise attack. (PICTURE, Vol. 2, p. 951)

The Gihon spring lay on the W side of the Kidron Valley, alongside what came to be called the City of David. Though outside the city walls, it was close enough that a tunnel could be excavated connecting to a shaft, enabling the city’s inhabitants to draw water without going outside the protective walls. This was done early in the city’s history, according to the archaeological evidence. In 1961 and 1962, excavations revealed a substantial early wall, situated below the upper end, or entrance, of the tunnel, hence enclosing it. It is thought to be the wall of the old Jebusite city.