National Park Krka Krka lies within Šibenik-Knin County, and covers a total area of 109 km² of the loveliest sections of the Krka River, and the lower course of the Čikola River. The national park is a vast and primarily unaltered area of exceptional natural value, including one or more preserved or insignificantly altered ecosystems. The purpose of the park is primarily to serve science, culture, education and recreation, while tourism activities have also been introduced for its visitors. Including the submerged part of the river at the mouth, the Krka River is 72.5 km long, making it the 22nd longest river in Croatia. It springs in the foothills of the Dinara mountain range, 2.5 km northeast of Knin. With its seven waterfalls and a total drop in altitude of 242 m, the Krka is a natural and karst phenomenon. The travertine waterfalls of the Krka River are the fundamental phenomenon of this river. The need to legally protect the Krka River and its exceptional natural values was already recognized in the mid 20th century. The initiative to proclaim the Krka River a national park was again launched in 1971, with the drafting of a physical plan entitled Krka National Park: physical development plan. On 24 January 1985, the Parliament of the Socialist Republic of Croatia proclaimed the area covering 142 km² from the Early Croatian fortresses of Trošenj and Nečven to the Šibenik Bridge, including 3.5 km of the course of the Čikola River, a national park. Due to four urban centres (Skradin, Bilice, Raslina and Zaton), the construction of the Zagreb–Split motorway and the development of tourism and other economic activities in the area, in 1997 the Croatian Parliament revised the park boundaries by passing the Act on Amendments to the Act on the Proclamation of Krka National Park.