Charles Ellicott Commentary Psalms 137:1

"By the rivers of Babylon, There we sat down, yea, we wept, When we remembered Zion." — Psalms 137:1 (ASV)

By the rivers ...—Mentioned as the characteristic feature of the country, as we say “among the mountains of Wales.” The canals which irrigated Babylonia made it what an ancient writer called it, the greatest of “cities of river places.”