Ulleungdo (also spelled Ulreungdo; Hangul: , ) is a South Korean island 120 km (75 mi) east of the Korean Peninsula in the Sea of Japan, formerly known as the Dagelet Island or Argonaut Island in Europe. Volcanic in origin, the rocky steep-sided island is the top of a large stratovolcano which rises from the seafloor, reaching a maximum elevation of at Seonginbong Peak. The island is in length and in width; it has an area of . It has a population of 10,426 inhabitants. The island makes up the main part of Ulleung County, North Gyeongsang Province, South Korea and is a popular tourist destination. The main city of Ulleung-do is the port of Dodong (), which serves as the main ferry port between Ulleung-do and the South Korean mainland. After tourism, the main economic activity is fishing, including its well-known harvest of squid, which can be seen drying in the sun in many places. History The island consists primarily of trachyandesite rock. A major explosive eruption about 9,350 years ago reached a Volcanic Explosivity Index of 6 and deposited tephra as far as central Honshū over away, while producing pyroclastic flows on the island and decapitating its top to form a caldera. Archaeological evidence indicates that the island has been inhabited since the 1st millennium BC. The first confirmed historical reference to Ulleung-do is in the Samguk Sagi for the year 512. In that year, the Silla general Kim Isabu conquered the island, which had previously been the autonomous nation of Usan-guk. Some accounts relate that he used a number of wooden lions to intimidate the population, threatening to turn them loose unless they surrendered. Usan-guk did not remain under the Silla rule, however, and the island did not become a permanent political part of Korea until 930, when it was annexed by Goryeo. Remote as it is from the Korean mainland, Ulleung-do was a recurrent security headache for the Goryeo and Joseon dynasties. It was devastated by Jurchen pirate raids in the 11th century, and by Wokou pirate raids in the 14th century. A clash with Japan over fishing rights in the 1690s was precipitated by the Korean fisherman An Yong-bok. In response to these difficulties, Joseon adopted an "empty-island" policy which however proved impossible to enforce. The empty-island policy was officially rescinded in 1881, after which the government sought to encourage additional settlement of Ulleungdo. American