Vale of Siddim
'The vale of Siddim, which is the salt sea' as in Genesis 14:3, signifies the filthiness of lusts and the falsities derived from them.
In Genesis 14:3, 8, this signifies the unclean things of evil desires. (Arcana Coelestia 1666)
(Referenser: Arcana Coelestia 1666 [1-4])