Banda Sea, portion of the western South Pacific Ocean, bounded by the southern islands of the Moluccas of Indonesia (Alor, Timor, Wetar, Babar, Tanimbar, and Kai on the south and Ceram, Buru, and Sula on the north). It occupies a total of 180,000 square miles (470,000 square km) and opens to the Flores (west), Savu (southwest), Timor (south), Arafura (southeast), and Ceram and Molucca (north) seas. The Banda Sea is divided into two basins separated by a ridge that is surmounted in places by coral reefs. The North Banda Basin is 19,000 feet (5,800 metres) deep, while the South Banda Basin is 17,700 feet (5,400 metres) deep. A volcanic ridge further divides the southern South Banda Basin from the Weber Basin, the deepest in the sea, at some 24,409 feet (7,440 metres). The active volcano, Mount Api, rises from the floor of the southern basin at14,800 feet (4,500 metres) to 2,200 feet (670 metres) above sea level. The clear waters surrounding many islands provide a perfect habitat for spectacular coral reefs.