Garden Island is a narrow island about 10 kilometres (6 mi) long and 1.5 kilometres (0.9 mi) wide, lying about 5 kilometres (3 mi) off the Western Australian coast, to which it is linked by an artificial causeway and bridge.

Rottnest Island, often colloquially referred to as "Rotto", is a 19-square-kilometre (7.3 sq mi) island off the coast of Western Australia, located 18 kilometres (11 mi) west of Fremantle. A sandy, low-lying island formed on a base of aeolianite limestone, Rottnest is an A-class reserve, the highest level of protection afforded to public land.