Short answers, pulled from the story.
The Vistula River rises at Barania Góra in the southern Silesian Beskids and flows for 651 kilometers to the Baltic Sea. It emerges from two distinct sources known as the White Little Vistula and the Black Little Vistula before beginning its journey.
The Vistula River served as the primary trading artery of Poland between the 10th and 13th centuries. During this period, salt, timber, grain, and building stone flowed northward along the river to connect the interior of Europe to the Baltic Sea.
The Prussian government constructed the Vistula Cut between 1889 and 1895 to divert the majority of the river's flow directly into the Baltic Sea. This artificial channel was designed to flush floating ice into the sea and prevent ice-jam floods.
The Vistula River basin was struck by one of the largest floods in modern Polish history in July 1997. Prolonged heavy rainfall caused extreme discharges that breached hundreds of kilometers of levees and damaged about 1,100 kilometers of flood embankments.
Princess Wanda is the legendary figure associated with the Vistula River in Polish folklore. According to the 15th-century historian Jan Długosz, she drowned herself in the river to prevent the German prince Rytigier from invading her country.