The Psel or Psyol is a river, a left tributary of the Dnieper, which flows through Russia and Ukraine.

The Dnieper, also called Dnipro or Dniapro, 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. Approximately 2,200 km (1,400 mi) long, with a drainage basin of 504,000 square kilometres (195,000 sq mi), it is the longest river of Ukraine and Belarus and the fourth-longest river in Europe, after the Volga, Danube, and Ural rivers.