Rockingham is a suburb of Perth, Western Australia, located 47 km south-south-west of the city centre. It acts as the primary centre for the City of Rockingham. It has a beachside location at Mangles Bay, the southern extremity of Cockburn Sound. To its north stretches the maritime and resource-industry installations of Kwinana and Henderson. Offshore to the north-west is Australia's largest naval fleet and submarine base, Garden Island, connected to the mainland by an all-weather causeway.