The Oder (; Czech and ) is a river in Central Europe. It rises in the Czech Republic and flows (generally north- and northwest-ward) through western Poland, later forming of the border between Poland and Germany, part of the Oder–Neisse line. The river ultimately flows into the Szczecin Lagoon north of Szczecin and then into three branches (the Dziwna, Swina and Peene) that empty into the Gulf of Pomerania of the Baltic Sea.