In the allotting of tribal territories, Jerusalem was on the boundary between Judah and Benjamin, the specific border running along the Valley of Hinnom. This would place at least what comprised the later “City of David,” situated on the ridge between the Kidron and Tyropoeon valleys, within the territory of Benjamin.

It seems that the Jebusites at that time had their city on the southern end of the eastern spur. They were confident of the impregnability of their fortress city, with its natural defenses of steep valley walls on three sides and, probably, special fortifications on the north. It was known as “the place difficult to approach” (1Ch 11:7), and the Jebusites taunted David that even ‘the blind and the lame of the city’ could hold off his attacks. 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) By whatever means, the city was taken and David moved his capital there (1070 B.C.E.). The Jebusite stronghold now came to be known as “the City of David,” also called “Zion.”​—2Sa 5:7.

David began a building program within the area, apparently also improving the city’s defenses. (2Sa 5:9-11; 1Ch 11:8) “The Mound” (Heb., ham·Mil·lohʼʹ) referred to here (2Sa 5:9) and in later accounts (1Ki 9:15, 24; 11:27) was some geographic or structural feature of the city, well known then but unidentifiable today.