2 Samuel 12:27

And Joab sent messengers to David, and said, I have fought against Rabbah, and have taken the city of waters.

The city of waters. Rabbah, like Aroer, was divided into two parts-one, the lower town, insulated by the winding course of the Jabbok, which flowed almost round it, and the upper and stronger town, called the royal city, from its being the seat of the Ammonite Government, and containing the palace of the king. Here was kept the iron bedstead of Og, as an antique relic, indicating the stature and strength of the gigantic king of Bashan. The first was taken by Joab, but the honour of capturing so strongly a fortified place as the other was an honour reserved for the king himself.