The rail network, which has been rebuilt and extended following its almost complete destruction during the Korean War, is the principal means of transportation, carrying nearly all of the nation's freight and most of its passenger traffic. In 2002, railways in use comprised 5,000 km (3,107 mi) of track. The principal lines run along the west coast from P'yongyang to Sinuiju and across the peninsula from P'yongyang to Wonsan, Hamhung, and Ch'ongjin. A northern line, completed in the early 1980s, links P'yongyang to Hyesan and Musan. The major trunk routes are electrified. A subway system opened in P'yongyang in 1973 and was expanded under the 1978-84 development plan. There are also train services to Moscow and Beijing.
Road transportation is of secondary importance. In 2002, highways totaled an estimated 31,200 km (19,388 mi), of which only 1,997 km (1,241 mi) were paved. The exceptions are a superhighway connecting P'yongyang with Kaesong and two multi-lane highways, which link the national capital with the ports of Wonsan and Namp'o.
Most of the nation's 2,253 km (1,400 mi) of navigable waterways are suitable for small craft only. Rivers utilized for freight transportation are the Yalu, Taedong, and Chaeryong. The principal ports are Namp'o on the west coast, and Ch'ongjin and Hungnam (Hamhung) on the east coast. In 2002, there were 122 ships in the merchant fleet, with a total capacity of 738,886 GRT (1,037,506 DWT). Also in 2001, there were 87 airports, of which 39 had paved runways. Limited air services connect P'yongyang with other cities within the DPRK and in China and the former USSR. In 2001, 78,800 passengers were carried on scheduled domestic and international flights.