Lake Gruner See or Green Lake is a karst lake in Styria that forms when the snow on the mountain slopes melts and the area slowly fills with crystal clear water. Exactly, while in winter the water completely disappears and the meadows full of hiking trails and benches are once again above the water level, and because of the unique turquoise color of this lake, it is also called the “Caribbean of the Alps”, and it is considered one of the most beautiful lakes It is the most visible in Austria, to the point that the beholder sees the deepest points at its bottom.