Covering a whopping 5600 square kilometres (four times the size of Greater London), Lake Vänern totally dominates the map of Sweden, stretching 140km in length from Trollhättan, northeast of Gothenburg, up to Karlstad. Travelling along the lake you could be forgiven for thinking you’re on the coast: the endless vistas of water and sky really do resemble those of the sea. Indeed, such is its size that the Swedish Met Office even produces a shipping forecast for the lake.
Vänern was created after the last Ice Age about ten thousand years ago. Very slowly, as the land began to rise following the retreat of the ice, islands formed in the extensive waters that once covered this part of southern Sweden. With further landrise, today’s familiar pattern of forest and lake gradually took shape. Consequently, Vänern – and neighbouring Lake Vättern – contain several species of marine life left over from the Ice Age and not normally found in freshwater lakes.