What looks like a lake and feels like a lake isn’t necessarily always a lake. Well, at least it’s not always that deep.
Welcome to Green Lake, Austria — a hiker-and-scuba-diver’s dream.
This body of water literally shape-shifts throughout the seasons. During the winter, it’s more like a shallow pond. But come spring, it gets deep enough to dive and swim in.
Eventually, what was once along the pond’s edge becomes submerged underwater, transforming the lake into an incredible underwater oasis.
Green Lake is surrounded by an Austrian village called Tragöß. It is a county park where hikers tromp through the lush Hochschwab mountains and forests year round.
When the snow in the nearby karst mountains begins to melt from rising temperatures in the spring, it trickles into the lake basin and fills it with water.
Come spring, snowmelt runoff makes the water extremely clean, clear, and cold, maintaining a steady chilly temperature of about 45 degrees Fahrenheit.
Grüner See literally translates to 'Green Lake,' a name that originates from this sparkling emerald green water.
A variety of water creatures live in the lake, including snails, water fleas, small crabs, fly larvae, and even some species of trout.
In June, the water level reaches its highest mark, at which point meadows of green flowers appear around the edges of the lake.
In the mid-to-late 90s, the Alliance For Nature started an initiative to put Green Lake under official legal protection to preserve the entire region surrounding the lake.
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