The Warta river starts in the Kraków-Częstochowa Upland at Kromołów near Zawiercie in the Silesian Voivodeship. It flows through Łódź Voivodeship, Greater Poland (Wielkopolska), and Lubusz Voivodeship. It empties into the Oder river in a town called Kostrzyn nad Odrą, on the border with Germany.