Lake Bohinj is the largest natural lake in Slovenia with endless opportunities for outdoor activities. It is located in a glacial valley and it comprises almost 100 million cubic metres of water – according to an old Bohinj joke: no more than a bucket if it is large enough. The steeply descending lake basin is relatively smoothly shaped and has no shallow areas. In summer, the temperature of the water rises to 22 °C; in winter, the lake freezes sometimes. Water level rises 2 – 3 metres after heavy rainfall.