Deuteronomy 4:41-49

Then Moses set apart three cities beyond the Jordan toward the sunrising; that the manslayer might flee thither, that slayeth his neighbor unawares, and hated him not in time past; and that fleeing unto one of these cities he might live: namely, Bezer in the wilderness, in the plain country, for the Reubenites; and Ramoth in Gilead, for the Gadites; and Golan in Bashan, for the Manassites. And this is the law which Moses set before the children of Israel: these are the testimonies, and the statutes, and the ordinances, which Moses spake unto the children of Israel, when they came forth out of Egypt, beyond the Jordan, in the valley over against Beth-peor, in the land of Sihon king of the Amorites, who dwelt at Heshbon, whom Moses and the children of Israel smote, when they came forth out of Egypt. And they took his land in possession, and the land of Og king of Bashan, the two kings of the Amorites, who were beyond the Jordan toward the sunrising; from Aroer, which is on the edge of the valley of the Arnon, even unto mount Sion (the same is Hermon), and all the Arabah beyond the Jordan eastward, even unto the sea of the Arabah, under the slopes of Pisgah.