Weissensee

The Weissensee is the highest bathing lake in the Alps at 930 meters altitude in Carinthia, and it has drinking-water quality because no motorboats are permitted. The surface is quiet year-round. In summer, water temperatures reach 24 degrees and about two-thirds of the shoreline remains undeveloped, with hiking access directly from the water’s edge into the Gailtaler Alpen. In winter, when the lake freezes fully, it becomes Europe’s largest natural ice-skating surface and hosts the Weissensee Ice Marathon, a 50-kilometer race that has been running since 1976. There is no direct train connection; you need a car or transfer from Greifenburg. That remoteness is part of the point. If you want a Carinthian lake experience without the boat traffic, beach bars, and July crowd of the Wörthersee, the Weissensee is the honest alternative.