This bizarre public park transforms into a pristine underwater world every year

If you have any affinity at all for beautiful lakes, hiking, or both of these things combined, you should probably book a flight to Green Lake, Austria, immediately.

It's 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 a majestic underwater oasis.