Valley of Aven. Lit. “Valley of Wickedness.” Possibly it refers to ancient Syrian Heliopolis, now called Baalbek, in the Beqaa Valley of Lebanon. It was apparently a center for sun worship.
Beth-eden. This was probably a district about 200 miles northeast of Damascus (not to be confused with the Garden of Eden, Gen. 2:8 note), and ruled by a Syrian vassal king. The point of the parallelism between the Valley of Aven and Beth-eden is to indicate that not only Damascus, but its territories as well, will be undone.
Syria . . . to Kir. The original home of the Syrians (9:7), Kir will become their place of exile.