'City of David' in the Bible

Nevertheless, David captured the stronghold of Zion, that is the city of David.

So David lived in the stronghold and called it the city of David. And David built all around from the Millo and inward.

And David was unwilling to move the ark of the Lord into the city of David with him; but David took it aside to the house of Obed-edom the Gittite.

Now it was told King David, saying, “The Lord has blessed the house of Obed-edom and all that belongs to him, on account of the ark of God.” David went and brought up the ark of God from the house of Obed-edom into the city of David with gladness.

Then it happened as the ark of the Lord came into the city of David that Michal the daughter of Saul looked out of the window and saw King David leaping and dancing before the Lord; and she despised him in her heart.