The Dead Sea - so named because no marine life can survive in it - is reachable from Tel Aviv in about two hours, and is well worth the trip. At 1,312 feet below sea level, it's the second most salty body of water on earth, which means that swimmers can float on the surface with no effort. A very popular destination with health nuts, the mud of the Dead Sea is rich with anti-oxidant minerals, leading people to slather themselves in it and spend some time suspended in the warm waters. There are several beaches along the coast, many with spas where you can receive other health treatments.