ESV - 20 Then the Lord said, "Because the outcry against Sodom and Gomorrah is great and their sin is very grave.
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
There is a video on youtube of Ron Wyatt (I believe) with a submarine/camera investigating the floor of the Dead Sea. It seems that one of these cities is now covered by the 'waters' of the Dead Sea.
I have seen a photograph taken from the hill above Sodom and Gomorrah that shows the residue of the brimstone (sulfur) in two locations on the shore of the Dead Sea.