Jerusalem means the city of God, the holy city, by the modern Arabs el-Khuds, meaning the holy; once the city of Judah.
2 Chronicles 25:28
Then they brought him on horses and buried him with his fathers in the city of Judah.
This name is in the original in the dual form, and means possession of peace or foundation of peace. The dual form probably refers to the two mountains on which it was built, Zion and Moriah; or, as some suppose, to the two parts of the city, the upper and the lower city. Jerusalem is a mountain city enthroned on a mountain fastness.
Psalm 68:15-16
A mountain of God is the mountain of Bashan;
A mountain of many peaks is the mountain of Bashan.
Why do you look with envy, O mountains with many peaks,
At the mountain which God has desired for His abode?
Surely the Lord will dwell there forever.
Psalm 87:1
His foundation is in the holy mountains.
Psalm 125:2
As the mountains surround Jerusalem,
So the Lord surrounds His people
From this time forth and forever.
Psalm 76:1-2
God is known in Judah;
His name is great in Israel.
His tabernacle is in Salem;
His dwelling place also is in Zion.
Psalm 122:3
Jerusalem, that is built
As a city that is compact together;
It stands on the edge of one of the highest table lands in Palestine, and is surrounded on the south-eastern, the southern, and the western sides by deep and precipitous ravines...