2 Samuel 10:8

The Syrians … were by themselves in the field. We learn from 1 Chronicles 19:7 that the rendezvous of the Arameans was at Medeba, a small town situated upon a hill in the Mishor, or treeless prairie land, called "the plain" in Joshua 13:16 . As it was four miles southeast of Heshbon, and more than twenty miles distant from Rabbah, it is plain that they were marching northward, and that Joab was only just in time to prevent a junction of the two armies. The Ammonites, who were expecting their allies, and knew of their approach, had come outside of Rabbah, but had only posted themselves in fighting order "at the entering in of the gate."