n which country would you find both the rivers Oder and Vistula, which flow into the Baltic Sea?
Poland the height of up to . The highest peak of the park is Rowokol ( above sea level). The longest rivers are the Vistula (), long; the Oder () which forms part of Poland's western border, long; its tributary, the Warta, long; and the Bug, a tributary of the Vistula, long. The Vistula and the Oder flow into the Baltic Sea, as do numerous smaller rivers in Pomerania. The Łyna and the Angrapa flow by way of the Pregolya to the Baltic Sea, and the Czarna Hańcza flows into the Baltic Sea through the Neman. While the great majority of
Baltic Sea the Baltic. They include the major rivers of north Europe, such as the Oder, the Vistula, the Neman, the Daugava and the Neva. Additional fresh water comes from the difference of precipitation less evaporation, which is positive. An important source of salty water are infrequent inflows of North Sea water into the Baltic. Such inflows, important to the Baltic ecosystem because of the oxygen they transport into the Baltic deeps, used to happen regularly until the 1980s. In recent decades they have become less frequent. The latest four occurred in 1983, 1993, 2003 and 2014 suggesting a new inter-inflow period