The Dead Sea , also called the Salt Sea, is a salt lake bordering Jordan to the east and Israel and Palestine to the west. Its surface and shores are 423 metres (1,388 ft) below sea level,Earth's lowest elevation on land. The Dead Sea is 377 m (1,237 ft) deep, the deepest hypersaline lake in the world. With 33.7% salinity, it is also one of the world's saltiest bodies of water, though Lake Assal (Djibouti), Garabogazköl and some hypersaline lakes of the McMurdo Dry Valleys in Antarctica (such as Don Juan Pond) have reported higher salinities. It is 9.6 times as salty as the ocean. This salinity makes for a harsh environment in which animals cannot flourish, hence its name. The Dead Sea is 55 kilometres (34 mi) long and 18 kilometres (11 mi) wide at its widest point. It lies in the Jordan Rift Valley, and its main tributary is the Jordan River.
The Dead Sea has attracted visitors from around the Mediterranean basin for thousands of years. Biblically, it was a place of refuge for King David. It was one of the world's first health resorts (for Herod the Great), and it has been the supplier of a wide variety of products, from balms for Egyptian mummification to potash for fertilizers. People also use the salt and the minerals from the Dead Sea to create cosmetics and herbal sachets. In 2009, 1.2 million foreign tourists visited on the Israeli side.
The Dead Sea seawater has a density of 1.240 kg/L, which makes swimming similar to floating.