Deuteronomy 4:41-43

Brenton(i) 41 Then Moses separated three cities beyond Jordan on the east, 42 that the slayer might flee thither, who should have slain his neighbour unintentionally, and should not have hated him in times past, and he shall flee to one of these cities and live: 43 Bosor in the wilderness, in the plain country of Ruben, and Ramoth in Galaad belonging to Gad, and Gaulon in Basan belonging to Manasse.