God chose Zion as the place where He would meet with His people in a special sense. He met with them by residing in the temple and having fellowship with them through His priests. Among all the mountains near Mt. Zion, this one was His choice for habitation, and as such was the foundation of His dealings with the Israelites. There were some beautiful hilly sites in Israel, but this one was the best because God chose to make it His abode. Other ancient Near Eastern nations believed their gods lived in beautiful high mountains such as Mt. Carmel and Mt. Hermon. Zion was the city of God because God chose to make His earthly residence there in the temple. [source][source][source]