borneo 338Borneo ( ˈ b ɔːr n i oʊ ) is the third-largest island in the world, with an area of 748,168 km 2 (288,869 sq mi), and population of 23,053,723 (2020 national censuses). [1] [2] [3] Situated at the geographic centre of Maritime SoutheastBorneo, the third largest island in the world, is divided between three countries: Indonesia (73 percent), Malaysia (26 percent), and Brunei (one percent).Your trip to Borneo