The Don River is the fourth-longest river in Europe. Its basin covers an area of 425 600 km2 (87% in Russia and 13% in Ukraine). The Don’s largest tributary is the Donets. Other important tributaries are the Voronezh, Khoper, and Medveditsa, and it is linked to the Volga by the Volga-Don Canal.
The source of the river is in Russia, southeast of Moscow near Tula. It then flows for a distance of about 1 950 km, through Voronej, crossing Rostov and entering the Gulf of Taganrog in the Sea of Azov. The Don River is linked to the Volga River by a canal (102 km) near Volgograd.