Croatia serves as a gateway to eastern Europe. It lies along the east coast of the Adriatic Sea and shares a border with Yugoslavia (Montenegro and Serbia), Bosnia & Herzegovina, Hungary, and Slovenia. The republic swings around like a boomerang from the Pannonian Plains of Slavonia between the Sava, Drava, and Danube Rivers, across hilly, central Croatia to the Istrian Peninsula, then south through Dalmatia along the rugged Adriatic coast. Croatia is made up of 20 counties, plus the city of Zagreb and controls 1,185 islands in the Adriatic Sea, 67 of which are inhabited.