Final answer:
Warsaw and Krakow lie on the Vistula River, which empties into the Baltic Sea near Gdansk.
Step-by-step explanation:
The river on which Warsaw and Krakow lie is the Vistula River. This river flows through Poland and eventually empties into the Baltic Sea near the city of Gdansk. Historically, the Vistula has been a significant route for trade and travel, linking interior cities to the broader maritime routes of the Baltic Sea. It flows through major Polish cities, including Krakow and Warsaw. Warsaw, the capital and largest city of Poland, is situated on both sides of the Vistula River. Krakow, another prominent Polish city known for its historical and cultural significance, is located along the river as well.