Rocky Island, Turquoise Salt Lake Assal, Djibouti

Low, low lake

Its name means 'honey' in Arabic, but the waters of this Djibouti lake are far from sweet. Rapid evaporation here in the desert, combined with a lack of outflow, give Lake Assal a salinity level as high as 40%—ten times as salty as the ocean. Assal is even saltier than the Dead Sea and almost as low-lying: its surface more than 500 feet below sea level, it's the lowest-elevation point in Africa.