Until 1962, when the city was connected by rail and highway with Seoul, Pusan, Taegu, and Taejŏn, it was primarily a fishing port and a market centre for agricultural products (especially pears) from the Ulsan plain and the delta of the T'aehwa River. By the end of the first five-year economic plan (1966), the city had become an open port, and major industrial plants had been built. Installations include a thermoelectric power plant, an oil refinery, and fertilizer, automobile, aluminum, nylon, synthetic textile, and thermoplastic resin factories, within an area of about 10 square miles (26 square km). The port of Pangŏjin, on Ulsan Bay, became part of Ulsan in 1962. Shipbuilding is carried on there. Pop. (1985) 551,014.