Joshua 13:8, 10, 24-28

with whom the Reubenites and the Gadites have received their inheritance, which Moses gave them, beyond Jordan eastward, even as Moses the servant of the LORD gave them

and all the cities of Sihon king of the Amorites, which reigned in Heshbon, unto the border of the children of Ammon

And Moses gave inheritance unto the tribe of Gad, even unto the children of Gad according to their families. And their coast was Jazer, and all the cities of Gilead, and half the land of the children of Ammon, unto Aroer that is before Rabbah; and from Heshbon unto Ramath-mizpeh, and Betonim; and from Mahanaim unto the border of Debir; and in the valley, Beth-aram, and Beth-nimrah, and Succoth, and Zaphon, the rest of the kingdom of Sihon king of Heshbon, Jordan and his border, even unto the edge of the sea of Chinnereth on the other side Jordan eastward. This is the inheritance of the children of Gad after their families, the cities, and their villages.