Numbers 21:12-16

12From there they set out and camped in the Wadi Zered.

13From there they journeyed on and camped on the other side of [the river] Arnon, which is in the wilderness that extends from the boundary of the Amorites; for [the river] Arnon is the boundary of Moab, between Moab and the Amorites.

14That is why it is said in the Book of the Wars of the Lord: “Waheb in Suphah, And the wadis of the Arnon [River],

15And the slope of the wadis That stretches toward the site of Ar And leans to the border of Moab.”

16From there the Israelites went on to Beer, that is the well where the Lord said to Moses, “Gather the people together and I will give them water.”