The Dnieper ((də)ˈniːpər), also called Dnipro (dəˈniːprəʊ), is one of the major transboundary rivers of Europe, rising in the Valdai Hills near Smolensk, Russia, before flowing through Belarus and Ukraine to the Black Sea. It is the longest river of Ukraine and Belarus and the fourth-longest river in Europe, after the Volga, Danube, and Ural rivers. It is approximately long, with a drainage basin of .
In antiquity, the river was part of the Amber Road trade routes. During the Ruin in the later 17th century, the area was contested between the Polish–Lithuanian Commonwealth and Russia, dividing Ukraine into areas described by its right and left banks. During the Soviet period, the river became noted for its major hydroelectric dams and large reservoirs. The 1986 Chernobyl disaster occurred on the Pripyat River, a tributary of the Dnieper, just upstream from its confluence with the Dnieper. The Dnieper is an important navigable waterway for the economy of Ukraine and is connected by the Dnieper–Bug Canal to other waterways in Europe. During the 2022 Russian invasion of Ukraine, certain segments of the river are part of the defensive lines between territory controlled by Russians and Ukrainians.
In English, Dnieper derives from Russian Dnepr, and Dnipro from the Ukrainian. The initial D in Dnieper is generally silent, although it may be sounded: ˈniːpə(r) or dəˈniːpə(r). The English pronunciation of Dnipro is dəˈniːprəʊ.
The name varies slightly in the local Slavic languages of the three countries through which it flows:
Дняпро, dnjaˈprɔ, or Днепр Dnyepr, ˈdnjɛpr
Днепр; formerly spelled Днѣпръ
Дніпро, ɟnjiˈprɔ; poetic Дніпр; formerly Дніпер Dniper, ˈɟnjiper, or older Днѣпръ (Dnipr, ˈdn(j)ipr)
These names are all cognate, deriving from Old East Slavic Дънѣпръ (Dŭněprŭ). The origin of this name is disputed but generally derived from either Sarmatian *Dānu Apara ("Farther River") in parallel with the Dniester ("Nearer River") or from Scythian *Dānu Apr ("Deep River") in reference to its lack of fords, from which was also derived the Late Antique name of the river, Danapris (Δαναπρις).