Joshua 18:19

Then the boundary passes on to the north of the shoulder of Beth-hoglah . And the boundary ends at the northern bay of the Salt Sea , at the south end of the Jordan : this is the southern border .

It then went to the northern slope of Beth Hoglah and came out at the northern bay of the Dead Sea, at the mouth of the Jordan in the south. This was the southern boundary.

And the border passed along to the side of Beth–hoglah northward : and the outgoings of the border were at the north bay of the salt sea at the south end of Jordan : this was the south coast.