Timeline of Albanian history to 1993 cooperation signed with Yugoslavia; Yugoslav advisers and grain begin pouring into Albania. October<br> 26 October: Two British ships destroyed by mines off Albania's coast in the Straits of Corfu, see Corfu Channel Incident, . November<br> Albania breaks diplomatic relations with the United States after the latter withdraws its informal mission. 1947 April May<br> A United Nations commission concludes that Albania, together with Bulgaria and Yugoslavia, supported communist guerrillas in the Greek Civil War; Yugoslav leaders launch verbal offensive against anti-Yugoslav Albanian communists, including Hoxha; pro-Yugoslav faction begins to wield power. July<br> Albania refuses participation in the Marshall Plan of the
Albanian Adriatic Sea Coast Illyrians, Ancient Greeks and Romans in Albania. Besides the churches, mosques, forts and historical buildings, the most popular heritage tourism attractions are the remains of the ancient city of Apollonia, the ancient fortress of Rozafa and the amphitheatre of Durrës. The Albanian Adriatic Sea Coast is home to the three largest seaports of the country. The largest cargo ports among them is the Port of Durrës, one of the largest in the Adriatic Sea, with annual passenger volume of approximately 1.5 million. The other seaports include Vlorë and Shëngjin. In addition, the ports serve a wide system of ferries, connecting