In a park, near the village of Tragöß in Austria, a unique and beautiful natural occurrence happens in the warmer summer months of every year. The lake in the valley, called Grüner See (or Green Lake), is only 1-2 meters deep in winter. In May and June, however, the melt-waters from the snow covered mountains flood the valley floor, submerging the whole park in crystal clear water up to depths of 12 meters. Understandably the park has become a haven for divers as visibility reaches up to 40 meters, but the temperatures from the melt-water reach as low as 4 degrees.
Luckily, thanks to the divers, we can enjoy a beautiful video of the sites without having to bear the temperature.