Albert Barnes Commentary Deuteronomy 3:29

"So we abode in the valley over against Beth-peor." — Deuteronomy 3:29 (ASV)

Beth-peor, that is, the house of Peor, no doubt derived its name from a temple of the Moabite god Peor which was situated there. It was no doubt near Mount Peor (Numbers 23:28) and also near the valley of the Jordan, perhaps in the Wady Heshban.