Ar'al, a salt-water lake in Asia, in Russian territory, about 150 mi. w. of the Caspian Sea. Of the numerous rivers which formerly emptied into it, two alone now reach it--the Amu-Darya or Oxus, and the Syr-Darya or Jaxartes. The lake contains an abundance of sturgeon and other fish. It has a large number of islands. Navigation on it is difficult because of the shallowness of the waters and the fierce and sudden storms from the northeast.