Yakushima (屋久島) is one of the Ōsumi Islands in Kagoshima Prefecture, Japan. The island, 504.88 km2 (194.94 sq mi) in area, has a population of 13,178. Access to the island is by hydrofoil ferry (7 or 8 times a day from Kagoshima, depending on the season), slow car ferry (once or twice a day from Kagoshima), or by air to Yakushima Airport (3 to 5 times daily from Kagoshima, once daily from Fukuoka and once daily from Osaka). Administratively, the whole island is the town of Yakushima. The town also serves neighbouring Kuchinoerabujima. The majority of the island is within the borders of the Kirishima-Yaku National Park.Yakushima's electricity is more than 50% hydroelectric, and surplus power has been used to produce hydrogen gas in an experiment by Kagoshima University. The island has been a test site for Honda's hydrogen fuel cell vehicle research. (There are no hydrogen cars stationed on the island but electric cars are run by the municipality.)