Oak Island, North Carolina is a town mostly on Oak Island (which also contains the town of Caswell Beach and the North Carolina Baptist Assembly at Fort Caswell) in Brunswick County, North Carolina; a small part of the town extends onto the mainland north of the island's bridge. 6,571 people lived there at the 2000 census. It was founded in 1999 by the consolidation of the towns of Long Beach and Yaupon Beach. Its main industry is tourism; the town has about 30,000-40,000 people in the summer.