It was after the flood. Date? (When Abraham was alive)
A city situated along the boundary of Canaan, which seem to have been the most prominent of five cities, all of which were apparently located at the low plain of Siddim. Many scholars believe that the original sites of Sodom and the other cities of the district now lie submerged beneath the waters of the Dead Sea, though some others recently have claimed that the ruins of the cities may be identified with sites along wadis to the East and south East of the Dead Sea.
Sodom and Gomorrah persisted in a course in defiance of Jehovah God. ''The cry of complaint about Sodom and Gomorrah,'' Jehovah declared, ''yes, it is loud and their sins, yes, it is very heavy.'' -Genesis 18:16, 20-23