Daebu Island is an island in the Yellow Sea, within the municipal borders of Ansan city, Gyeonggi province. It has a population of roughly 7,114 people and an area of 41.98 km². Due to rising mudflats, the island has merged with neighbouring Seongam-do and Tan-do. Administratively, the island today is divided into five dong: Daebubuk-dong, Daebunam-dong, Daebudong-dong, Seongam-dong and Pungdo-dong. The predominant industries are tourism and fishing. The island is connected to the mainland in the south-east by road bridges, to Hyeong-do in the north-east by several routes due to land reclamation efforts, and to Seonjae-do to the west by a further road bridge.