The Wda is a river in Poland; it has a lowland character. The Wda is one of the 15 main canoe trails in Poland. It is 198 km long and the surface of its catchment area amounts to 2325 km2. The Wda's average gradient is 0.7‰ and its flow is 6.52 m3/s.

The Vistula is the longest river in Poland and the ninth-longest in Europe, at 1,047 kilometres in length. Its drainage basin, extending into three other countries apart from Poland, covers 193,960 km2 (74,890 sq mi), of which 168,868 km2 (65,200 sq mi) is in Poland.