Aside from being one of Croatia's most famous national parks, Plitvice Lakes National Park is also a UNESCO World Heritage Site. The entry fee is 13 euros and there are discounts for students and small groups. We got there thinking we'd spend a few hours at most, but we enjoyed it so much that we spent all day there. Once inside, you walk from lake to lake on elevated wooden bridges...even the trails through the woods are elevated. In effort to minimize man's impact on this natural place, most visitors never actually touch the grounds. The lakes all flow into one another before finishing in a river. There are various routes and there are signs giving you estimates of length (around 2hrs for the shortest and 8 for the whole tour). Sometimes, it's better to cross a lake on a boat to go quicker, the price of which is included in the ticket.