Port Arthur is a small town on the Tasman Peninsula, in Tasmania, Australia. It is about 80 km south east of the state capital, Hobart. It was settled as a penal colony (a very large prison for convicts). Port Arthur is now one of Australia's most important historic areas. In 2010 it was included on the UNESCO list of World Heritage Sites as one of the Australian Convict Sites. It is officially Tasmania's top tourist attraction. In 1996 the worst mass murder in Australian history took place here.