In Austria there is a surprising place – Gruner See (Green Lake). From August to April – it is a green park with paths, benches, green meadows. In the spring the water level in the lake rises strongly because of melting snow, an average of 3-4 meters, flooding annually paths, lawns, bridges and benches. But this visibility remains quite magical – 30 meters, probably, if not more. It was at this time should there be, to witness the crystal clear fresh water lakes.