 In addition to those, a large number of minor ports serve an extensive system of ferries connecting numerous islands and coastal cities in addition to ferry lines to several cities in Italy.The largest river port is Vukovar, located on the Danube, representing the nation's outlet to the Pan-European transport corridor VII.There are of crude oil pipelines in Croatia, connecting the Port of Rijeka oil terminal with refineries in Rijeka and Sisak, as well as several transhipment terminals.