Vänern is the largest lake in the European Union by area.
Sweden’s Vänern covers approximately 5,650 square kilometres, making it not only the EU’s largest lake but also Sweden’s largest. In Europe as a whole, it ranks behind Russia’s Lake Ladoga and Lake Onega, which are outside the European Union.
The lake lies in southwestern Sweden across the historical provinces of Värmland, Västergötland, and Dalsland. Its main inflow is the Klarälven, which begins in Norway, and its outflow is the Göta älv, flowing west to the Kattegat near Gothenburg.
Vänern is a glacially shaped lake with a maximum depth of about 106 metres and an average depth of roughly 27 metres. It contains numerous islands and skerries, including the large island of Kållandsö and the Djurö archipelago. The Göta Canal links Vänern with Vättern and Sweden’s Baltic-facing waterways, so the lake is both a major natural feature and part of an important historic transport route.