Traditionally, this is the cave in which David hid from Saul.
The following two pictures are of the Dead Sea Processing Plant. It is the only company that has access to the minerals in the Dead Sea, and is a multi billion dollar business. There are evaporating ponds where the water evaporates and the salt is left behind to be retrieved by a machine. Here you can see some piles of the salts that are so valuable. (funny story, a Jewish guy in the mall at the Dead Sea kiosk asked Karen and I if we had ever heard of the dead sea, and we said "yes we were there just a few months ago". He was surprised, but continued with his sales pitch, but was very glad that we had visited his homeland).