Morava River, river in Serbia, formed by the confluence of the South (Južna) Morava and West (Zapadna) Morava rivers. It follows a 137-mile (221-kilometre) course, mainly northerly, to enter the Danube River near Smederevo. North of Lapovo the Morava opens into the wide, meandering Pomoravlje valley, a fertile agricultural region. The total area of the Morava River basin is some 14,500 square miles (37,500 square km), almost corresponding to the political definition of Serbia.
The West Morava originates in southern Serbia and North Macedonia on the west-facing slope of Golija Mountain. Three hydroelectric stations are located along its 185-mile (298-kilometre) course. The South Morava is 198 miles (319 km) long from its source at the union of the Binačka Morava and Moravica rivers. Lake Vlasina on the Vlasina, a tributary, provides water for four hydroelectric stations. The Nišava, another tributary, rises in western Bulgaria; its valley provides an important transportation route from Belgrade via Sofia to Turkey. The Morava and the South Morava together are a vital part of the Morava-Vardar (Axiós) corridor, a main road and rail route in Serbia.