Croatia is a country of approximately 4.3 million people located in southern Europe. Although independent for brief periods of time since the Middle Ages, in modern times Croatia was part of the former communist Yugoslavia until 1991. Today, Croatia is a modern democratic, parliamentary republic, a member of NATO and the European Union. For such a small country, Croatia's landscape is very diverse and renowned for its beauty. Northern Croatia lies on the southern edge of Panonnian Basin and is characterized by open farmland interrupted by rivers (Drava, Sava & Danube, being the largest) and karstic hills. Coastal Croatia (Istria, Kvarner & Dalmatia), with its thousands of islands, is spectacularly beautiful with dramatic mountains rising from the waters of the Adriatic sea. In between coastal and northern Croatia lie the upland regions of Lika and Gorski Kotar, whose cold winters and mild summers are in marked contrast to the hot summers and mild winters of the nearby coast.