Numbers 22:36
36 When Balak heard that Balaam had come, he went out to meet him at the city of Moab, fon the border formed by the Arnon, at the extremity of the border.
Judges 11:18
18 “Then they journeyed through the wilderness and vwent around the land of Edom and the land of Moab and warrived on the east side of the land of Moab and xcamped on the other side of the Arnon. But they did not enter the territory of Moab, for the Arnon was the boundary of Moab.