Wonsan (wŭnˈsän) [key], Jap. Gensan, city (1993 pop. 300,148), capital of Kangwon prov., SE North Korea, on the Sea of Japan (or East Sea). It is a major port and naval base, with a natural harbor protected by a line of islands. The city has important fish and fish-processing industries. Oil refining, rice processing, and the manufacture of locomotives, textiles, ships, chemicals, and leather goods are also important. Opened to foreign trade in 1883, Wonsan became a Japanese naval base in World War II. It suffered heavy damage during the Korean War.