Gorski Kotar (Croatian: Gorski kotar, pronounced [ɡǒrskiː kôtaːr] gor-SKI ko-TAR; 'Highlands' or 'Mountain District') is the mountainous region in Croatia between Karlovac and Rijeka. Because 63% of its surface is forested it is popularly called the green lungs of Croatia or Croatian Switzerland. Through the region passes the European route E65, which connects Budapest and Zagreb with the Adriatic Port of Rijeka.