The Pregolya River in Gvardeysk.
|⁃ location||Instruch and Angrapa confluence|
|Basin size||15,500 km2 (6,000 sq mi)|
|⁃ average||90 m3/s (3,200 cu ft/s)|
It starts as a confluence of the Instruch and the Angrapa and drains into the Baltic Sea through the Vistula Lagoon. Its length under the name of Pregolya is 123 km, 292 km including the Angrapa. The basin has an area of 15,500 km². The average flow is 90 m³/s.