Tonga ISO 3166-1 code TO Region PolynesiaSubdivisionsDivision 'EuaHa'apaiNiuasTongatapuVava'u Child topics: 'Eua (Tongan division)Ha'apai (Tongan division)Niuas (Tongan division)Tongatapu (Tongan division)Vava'u (Tongan division) Parent topics: Polynesia