Construction was in progress in 1970 on a line that will connect Elbasan with Prrenjas, which is just over five miles from Lake Ohrid. This line follows the route of the old Roman Via Egnatia, and in later programs it will probably be extended to Lin, on the lake, and then southward to Korce. When these lines are completed, they and the road network will provide vastly improved internal communications, but many small areas within the North Albanian Alps and the higher central and eastern mountains will remain difficult to reach. Pipeline During the mid-1930s the Italian state-owned petroleum company constructed a forty-four-mile, eight-inch pipeline to connect the oilfields in the Stalin area with the port of Vlore. The line had a capacity of about 5,000 barrels a day and carried crude for transshipment to refineries in Italy. In the early 1950s the line was extended northward to the newly built refinery at Cerrik. Airlines In the early post-World War II period when Albania was practically a vassal state of Yugoslavia, regular air traffic was established between Belgrade and Tirana. After the estrangement of Yugoslavia from the Soviet Union, when Albania became a satellite of the Soviet Union, regular traffic was set up between Tirana and Moscow and, to a lesser degree, between Tirana and the capitals of the Eastern European Communist countries other than Belgrade. When Albania became aligned with Communist China, direct connections with almost all external points were severed. Even Peking flights were routed via intermediate stops in Italy, usually Bari or Rome. Between 1967 and 1970 connections between Albania and most of the Eastern European countries, but not the Soviet Union, were gradually restored. Service is scheduled but infrequent. Weekly flights are typically connected through Belgrade. Traffic elsewhere is ordinarily routed via Italy. Albanian officials depart and reenter the country via Bari or Rome, connecting to Tirana on a scheduled Alitalia flight or by an Albanian flight. Internal air services are also limited. Those available are centered on Tirana. Merchant Shipping Because no railway leaves the country and border-crossing roads are inadequate, nearly all foreign trade is carried by sea. Durres and Vlore are the major ports. Durres has a first-class harbor, warehouses, petroleum storage tanks, a shipbuilding capability, and railway spurs to the docks. Vlore is a better natural port and is the terminus of the oil pipeline. It has fewer port facilities than Durres, however, and no rail connections with the rest of the country. Sarande, Shengjin, and Porte Palermo are less important ports. Only the Drin and Buene rivers might be considered navigable to any degree and even then only for small ships and short distances. Lake Scutari and the interior lakes are navigable but are of little commercial use. Smaller oceangoing craft are used in a limited amount of coastal trade.