There are underground lakes where the water is 100% saturated brine making it impossible to dive down into and as in the dead sea you simply float on top. Our guide told a story of a group of partying soldiers who whent onto this lake in a boat and while playing around capsised the boat trapping themselves underneath the upturned hull. They had not the strength to push the boat upright and were unable to dive down to swim under so all seven eventually ran out of oxygen and suffocated. Boats , she said are no longer allowed on the lakes.
