Joshua 15:2
And their south border was from the shore of the salt sea, from the bay that looketh southward:
More from Joshua 15
This then was the lot of the tribe of the children of Judah by their families; even to the border of Edom the wilderness of Zin southward was the uttermost part of the south coast.
And it went out to the south side to Maalehacrabbim, and passed along to Zin, and ascended up on the south side unto Kadeshbarnea, and passed along to Hezron, and went up to Adar, and fetched a compass to Karkaa:
From thence it passed toward Azmon, and went out unto the river of Egypt; and the goings out of that coast were at the sea: this shall be your south coast.
And the east border was the salt sea, even unto the end of Jordan. And their border in the north quarter was from the bay of the sea at the uttermost part of Jordan: