The district of Southern Adelaide is located at the southern part of the Greater Adelaide metropolitan area, which includes the following local government areas: the City of Holdfast Bay, the City of Marion, the City of Mitcham and the City of Onkaparinga. The region has a particular focus on its natural wonders, with a lot of coastal suburbs, parks and gardens that 400,000 residents can enjoy. Mitcham is only one of three Australian suburbs to be awarded a “Tree Cities of the World” honour from the Food and Agriculture Organisation of the United Nations, due to their commitment in preserving urban forests. The region also displays their dedication to honouring the Aboriginal history of the land, naming the Onkaparinga River after a Kaurna word that means “women’s river”. Holdfast Bay is also known for having a Japanese sister city named Hayama, Kanagawa.