Joshua 13:8-10

8The tribes of Reuben and Gad with half of the tribe of Manasseh had received their inheritance east of the Jordan River, since the Lord’s servant Moses had already given it to them.

9The border extended from Aroer on the edge of the Arnon Valley, including the city in the middle of the valley, and the whole plateau from Medeba to Dibon.

10It included all the cities of King Sihon of the Amorites up to the border of Ammon. Sihon’s capital was Heshbon.