Zion is often described as a “hill”, no doubt, in reference to the temple being built on the hill of Zion (Psalm 2:6; 3:4; 15:1; 43:3; 99:9). Zion, which probably means “citadel”, occurs over 150 times in the Old Testament. It was one of the hills, located in the southeast section, on which Jerusalem stood (i.e. Acra, Bezetha, Moriah, Olivet, Ophel, Scopus, and Zion).
David brought the ark to Zion, and the hill henceforth became sacred (2 Samuel 6:10-12). When Solomon later moved the ark to the temple on nearby Mt. Moriah, the name Zion was extended to take in the temple (Isaiah 8:18; 18:7; 24:23; Joel 3:17), and it was looked on by the people as the dwelling place of God. Zion later came to stand for all of Jerusalem (2 Kings 19:21; Psalm 133:3).
Zion played an important role in the Messianic prophecies of the Old Testament (Psalm 2:6; 110:2; Joel 2:32; Isaiah 61:3). In one sense, the redeemed have reached Zion, the church, pointed to by the prophets (Revelation 14:1). In another sense, Zion still lies ahead (Revelation 21:2), and we’re marching to it.