Adelaide is the capital city of South Australia, the state's largest city and the fifth-most populous city of Australia. "Adelaide" may refer to either Greater Adelaide or the Adelaide city centre. The demonym Adelaidean is used to denote the city and the residents of Adelaide. Adelaide city centre was originally inhabited by a group of Kaurna people and known as Tarndanyangga – now the dual name of Victoria Square in the middle of the city – or Tarndanya.
Adelaide is situated on the Adelaide Plains north of the Fleurieu Peninsula, between the Gulf St Vincent in the west and the Mount Lofty Ranges in the east. Its metropolitan area extends 20 km from the coast to the foothills of the Mount Lofty Ranges, and stretches 96 km from Gawler in the north to Sellicks Beach in the south.
Named in honour of Queen Adelaide, the city was founded in 1836 as the planned capital for the only freely-settled British province in Australia. Colonel William Light, one of Adelaide's founding fathers, designed the city centre and chose its location close to the River Torrens.