by being granted a visa, unlawful non-citizens must be removed from Australia as soon as reasonably practicable. The Australian government claims that immigration detention is not used to punish people. Instead, they claim it is an administrative function whereby people who do not have a valid visa are detained while their claims to stay are considered or their removal is facilitated. There are, or were, centres located at: Maribyrnong, established at Melbourne in 1966. Villawood, established at Sydney in 1976. Perth, established in 1981. Christmas Island, established 2001. Northern, established at Darwin in 2001. Baxter, near Port Augusta, SA, established 2002, closed 2007. Wickham Point, established at Darwin in 2011. Curtin, near Derby, WA, reopened in 2010. Scherger, near Weipa, Queensland, opened 2010, closed 2014. Yongah Hill, near Northam, WA, established in 2012. Immigration Residential Housing Centres (IRHC) Immigration residential housing provides an option for accommodating people in independent family-style housing in a community setting while still formally being detained. This type of facility is one of several types of alternative residential accommodation for detained people, subject to them meeting eligibility criteria. Perth Sydney Port Augusta Immigration Transit Accommodation Centres (ITAC) The Brisbane Immigration Transit Accommodation opened in November 2007 and the Melbourne Immigration Transit Accommodation opened in June 2008. Further immigration transit accommodation opened in Adelaide in 2011. ITCs are for short-term, low-risk detainees, however the Melbourne facility was extended with a high-security compound in 2018. Brisbane Melbourne Adelaide Alternative Places of Detention (APOD) Alternative Places of Detention (APOD) can accommodate any person who is in immigration detention. APOD may range from hospital accommodation in cases of necessary medical treatment, schools for the purpose of facilitating education to school-aged minors, rented accommodation in the community (hotel rooms, apartments), or accommodation in the community made available through arrangements with other government departments. Darwin Inverbrackie Leonora Christmas Island Pacific Solution facilities Since the implementation of the Pacific Solution Australia also funded immigration detention centres on: Manus Regional Processing Centre, Papua New Guinea closed in February 2008, re-opened on 22 November 2012 (re-closed on 23 November 2017). Nauru Regional Processing Centre closed in February 2008, re-opened in 2012. Services to immigration centres Most facilities were operated by Australasian Correctional Management (a subsidiary of G4S) under contract from the Department of Immigration until 2003, when ACM exited the market. Between 2003 and 2009, G4S was appointed as the contractor to manage a large