In winter, the Grüner See, or Green Lake, of Styria, is a small, three-foot-deep body of water surrounded by hiking trails and snow-covered mountains. In spring, visitors bring their SCUBA tanks and flippers — each year, melted snow and ice flows into the lake, increasing its depth by 30 feet and transforming it into an alpine diving spot.
The best time to dive in the Green Lake is during May and June, when the water level peaks. The benches, bridges, and paths that surround the lake in winter become submerged, lending an Atlantis feel to the adventure. The water itself has a brilliant turquoise tint, and is clear enough for you to see the sun-dappled grass covering the lake bed.
It's like having a piece of the Caribbean in the Alps — except that the water temperature is around 46 degrees Fahrenheit.
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