Hachijō-jima (八丈島) is a volcanic Japanese island in the Philippine Sea. It is about 287 km (178 mi) south of the special wards of Tokyo. It is part of the Izu archipelago and within the Fuji-Hakone-Izu National Park. Its only municipality is Hachijō. On 1 March 2018, its population was 7,522 people living on 63 km2. Some inhabitants speak Hachijō language, which is considered an endangered language and the number of speakers is unknown. The island has been inhabited since the Jōmon period, and was used as a place of exile during the Edo period. In modern times, it has been used for farming sugarcane and housing a secret submarine base during World War II; it is now a tourist destination within Japan.