National park Plitvice lakes in a particular geological and hidrogeologhical karst phenomena. Plitvice lakes were declared a national Park 8. April 1949. year. It is the largest, oldest and most popular Croatian national park. Is forested mountain terrain, which is 16 lakes of various sizes, filled with insight, green color. Lakes receive water from numerous rivulets and streams, and mutually connected by cascades and waterfalls. Barriers that have formed over tens of thousands of years, one of the main features of the park. Special geographical location and specific climatic features have contributed to the formation of many natural phenomena and rich biodiversity. Upper lakes, in the South predominantly consist of dolomite, and Lower lakes in the north of limestone.