Judges 11:16, 18

When the people of Israel arrived at Kadesh on their journey from Egypt after crossing the Red Sea

“Finally, they went around Edom and Moab through the wilderness. They traveled along Moab’s eastern border and camped on the other side of the Arnon River. But they never once crossed the Arnon River into Moab, for the Arnon was the border of Moab.