Joshua 18:15

18:15 The southern side started on the edge of Kiriath Jearim and extended westward to the spring of the waters of Nephtoah.

Joshua 18:20

18:20 The Jordan River borders it on the east. These were the borders of the land assigned to the tribe of Benjamin by its clans. ¹ 

[18:20]  ¹ tn Heb “This was the inheritance of the sons of Benjamin by its borders round about, by their clans.”