Depending on the size and location of the lake, the temperatures of Tirol's bathing lakes vary greatly. On average the water temperature is anywhere between 19°C and 25°C, though lakes range from icy cold to pleasantly warm in summer. In addition to the higher mountain lakes, Tyrol's largest lake, Lake Achensee, and the idyllically situated Vilsalpsee in the Tannheimer Tal Valley, are also considered among the region's colder bathing lakes. Water temperatures often do not reach more than 17 degrees. The warmest bathing lakes, on the other hand, reach much higher temperatures. The Schwarzsee near Kitzbühel, for example, has temperatures of up to 27 degrees in the summer months, the Walchsee in Kaiserwinkl up to 24 degrees and the Natterersee near Innsbruck warms up to 25 degrees.