Plitvice Waterfalls in September

May through September offers the best weather and longest daylight hours, but also the biggest crowds. July and August see 15,000 visitors per day - the boardwalks become human conveyor belts. If you can swing it, visit in late May or early September. You'll get warm weather, full water flow, and manageable crowds. Early morning is magic hour. The park opens at 7 AM, and that first hour before the tour buses arrive feels like you have the place to yourself. The light filtering through the forest canopy hits the waterfalls just right, and you can actually hear the water over the sound of conversation. Winter brings a completely different experience. The waterfalls partially freeze into ice sculptures, and the reduced crowds mean you can take your time. But some trails close due to ice, and daylight hours are short. Spring is underrated - April sees the waterfalls at their most powerful from snowmelt, though some higher trails might still be muddy.