The longest river in Poland and the longest river draining into the Baltic Sea is the Vistula.
The Vistula is about 1,047 kilometres long. It rises in the Silesian Beskids of southern Poland, flows through Kraków and Warsaw, and reaches the Baltic at Gdańsk Bay through a broad delta. Its basin extends beyond Poland into Belarus, Ukraine, and Slovakia, although most of the basin lies in Poland.
The river has been central to Polish transport, trade, and national identity. In the sixteenth and seventeenth centuries, grain moved down the Vistula toward Gdańsk, one of the Baltic’s major ports. The river also gave its name to the Vistulian, or Weichselian, glaciation recognized in northern Europe.
The Oder is a frequent mix-up because it is another major Polish river that reaches the Baltic. The Bug and Warta are important tributaries or regional rivers, but neither is longer than the Vistula.