It is located 240 km (150 mi) to the south of the Australian mainland, separated by Bass Strait. The state includes the main island of Tasmania, the 26th-largest island in the world, and the surrounding 334 islands.The state has a population of 507,626 (as of June 2010), almost half of which resides in the Greater Hobart precinct, which forms the metropolitan area of the state capital and largest city, Hobart.he state is named after Dutch explorer Abel Tasman, who made the first reported European sighting of the island on 24 November 1642. Tasman named the island Anthony van Diemen's Land after his sponsor Anthony van Diemen, the Governor of the Dutch East Indies.