Frozen waterfalls in Plitvice Lakes National Park, Croatia

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Waterfalls turned waterfreeze. Plitvice Lakes National Park, Croatia

Why visit one lake when you can visit 16? Plitvice Lakes National Park in Croatia serves up stunning terraced lakes connected to one another by more than 90 cascades and waterfalls, thanks to the unique geology of the area.

The surrounding mountains funnel water carrying calcium carbonate into the park. This accumulates and hardens over time into a type of limestone called tufa, which creates a series of barriers. These natural dams form pools, with thin, lacy waterfalls leading from one 'lake' to another. This majestic display draws more than a million visitors a year to the paths and boardwalks that wind through the lakes, a UNESCO World Heritage Site. Even in winter, the lakes retain their beauty, with once-roaring waterfalls frozen in place.