Grüner See (Green Lake) is a lake in Styria, Austria, surrounded by the Hochschwab Mountains and forests. The name “Green Lake” originated because of its emerald-green water. During winter, the lake is only 1–2 m (3–7 ft) deep and the surrounding area is used as a county park. However, in spring, when the temperature rises and snow melts, the basin of land below the mountains fills with water. The lake reaches its maximum depth of around 12 m (39 ft). The waters are at their highest in June when it becomes a destination for divers keen to explore the rare phenomenon. A bridge and a bench could also be found underwater, as well as trails and trees.