Genesis 14:10
And the vale of Siddim slimepits; and the kings of Sodom and Gomorrah fled, and fell there; and they that remained fled to the mountain.

Genesis 14:3
All these were joined together in the vale of Siddim, which is the salt sea.

Genesis 14:8
And there went out the king of Sodom, and the king of Gomorrah, and the king of Admah, and the king of Zeboiim, and the king of Bela (the same Zoar;) and they joined battle with them in the vale of Siddim;