Australia has three architectural listings on UNESCO's World Heritage list: Australian Convict Sites (comprising a collection of separate sites around Australia, including Hyde Park Barracks in Sydney, Port Arthur in Tasmania, and Fremantle Prison in Western Australia); the Sydney Opera House; and the Royal Exhibition Building in Melbourne. Contemporary Australian architecture includes a number of other iconic structures, including the Harbor Bridge in Sydney and Parliament House, Canberra. Significant architects who have worked in Australia include Governor Lachlan Macquarie's colonial architect, Francis Greenway; the ecclesiastical architect William Wardell; the designer of Canberra's layout, Walter Burley Griffin; the modernist Harry Seidler; and Jørn Utzon, designer of the Sydney Opera House. The National Trust of Australia is a non-governmental organisation charged with protecting Australia's built heritage.