A wall or fortress, a place to which Tiglath-pileser carried the Syrians captive after he had taken the city of Damascus (2 Kings 16:9; Amos 1:5; 9:7). Isaiah (22:6), who also was contemporary with these events, mentions it along with Elam. Some have supposed that Kir is a variant of Cush (Susiana), on the south of Elam.
Kir
Kir is a distant land the prophets mention in passing. Amos 1:5 says the people of Syria will go into captivity “unto Kir”, and Amos 9:7 asks Israel a surprising question: “Have not I brought up Israel out of the land of Egypt? and the Philistines from Caphtor, and the Syrians from Kir?” God was working in other nations’ histories as well. In Isaiah 22:6, Kir is named with Elam as a people of war who bring shield and quiver. Kir never becomes a story of its own. It is a name that reminds Israel how wide God’s attention reaches.
3 verses
Isaiah
And Elam bare the quiver with chariots of men and horsemen, and Kir uncovered the shield.
Amos
I will break also the bar of Damascus, and cut off the inhabitant from the plain of Aven, and him that holdeth the sceptre from the house of Eden: and the people of Syria shall go into captivity unto Kir, saith the LORD.
Are ye not as children of the Ethiopians unto me, O children of Israel? saith the LORD. Have not I brought up Israel out of the land of Egypt? and the Philistines from Caphtor, and the Syrians from Kir?
From Easton's Bible Dictionary
Matthew George Easton, 1897