What is "salsvatnet"

Salsvatnet is a lake in the municipalities of Fosnes and Nærøy in Nord-Trøndelag county, Norway. With its deepest depth of , it is Norway’s and Europe’s second deepest lake, after Hornindalsvatnet. Alternate sources give the depth as either or at the deepest point. The lake sits very close to the ocean, about above sea level at the surface and reaches to a depth of below sea level. It is a very large lake with an area of , a volume of , and a shoreline that is around.

Salsvatnet is a meromictic lake, meaning that the water is permanently stratified, often without oxygen in the lower depths ( bottom water) due to density gradient and a lack of turnover. A meromictic lake often preserves records of the geologic past. The lower layer of the lake is highly saline and as a result denser than the higher levels of water. Other meromictic lakes in Norway with old seawater in the lower depths include Kilevann, Tronstadvann, Botnvatnet, Rørhopvatnet, and Rørholtfjorden.