Plitivice is a gorgeous park located in Croatia's interior. It was crowded and the boardwalks through the park required you to watch where you put your feet! It was one of the most beautiful places I've seen in the world. It was very hot end of June but glad I went to see it. There was no interpretive center and I hope they establish one in the future. The falls are created by Karst, limestone and oxygen in the water. Stuff grows on plants and creates boundries so waterfalls occur. The waterways are constantly changing. I loved the sound of the water as we walked throughout. We also took a ferry type ride across the lake on our way back to the bus. They also had a tram that took you to a starting point of the hike. Worth a stop if you are traveling in Croatia. Your guide book can explain the biology with more exact information on how the falls form.