Sea Of Aral, a large inland sea or lake of Asiatic Russia and Turkistan, between lat. 42° 30' and 47° N., and lon. 57° 30' and 61° 30' E. It lies about 40 feet above the ocean, and more than 100 feet above the Caspian sea, from which it is 200 m. distant at the nearest point, and with which Humboldt and others suppose it to have been formerly connected. The Aral, covering an area of about 24,000 sq. m., is, next to the Caspian, the largest inland sea of the eastern hemisphere. It is shallow, with many islands. It has no outlet, but the Sir Darya or Sihoon (the Jaxartes of the ancients), the Amu Darya or Jihoon (the Oxus), and several smaller rivers flow into it. The water is brackish, but is freely drunk by horses, and is used for culinary purposes. Fish are abundant. The navigation of the sea of Aral is exceedingly difficult for sailing vessels; perfect calms alternate with violent and sudden storms, oftenest coming from the northeast. The harbors and anchorages are few and insecure. The shores are generally low and sandy, but on the northern side are small hills of clay. Its borders are generally uninhabited in summer, but in winter they are frequented by nomadic tribes from the Kirghiz steppes. The sea of Aral is in the power of the Russian empire.

The Russians explored and made a map of it as early as 1740, and they sent occasional expeditions to its borders till 1847, when they built a fort at the mouth of the Sir, and began to take military possession of the principal islands of the lake. Colonies were soon afterward founded, and Russian vessels began the regular navigation which they have since continued.