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.
From July through about mid-May, the lake looks like this.
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