A gaol at Pentridge was established in 1850 to house convicts sentenced by the courts to hard labour on the roads - convicts who previously were sent to Sydney to serve their sentences. The site was chosen for its proximity to Melbourne on the Sydney Road and for the abundance of local bluestone for use in road-making.
Many Pentridge buildings were designed partly on the panopticon principle, using a radial or cruciform plan to allow surveillance from a central point. The model prison at Pentridge 'B' Division, built in 1859, operated on the principle of total separation of prisoners during their confinement. Inspectors-general saw Pentridge as a terror to evil-doers, but residents of the village of Pentridge were not enamoured of its convict stigma and agitated unsuccessfully for its removal. They did succeed in having the suburb name changed to Coburg in 1870. Pentridge was variously known as 'the Pen', 'the Bluestone College' and 'the Big House'. In 1853 it held 229 prisoners, controlled by 56 penal officers, and in 1894 it held 565 male prisoners. Women were incarcerated in the new Female Gaol, known as 'the Fem', and were imprisoned mainly for vagrancy, prostitution or drunkenness. In the late 19th century Pentridge had a school with several teachers and housed within its walls a reformatory for Protestant girls and the Jika Reformatory for boys, where children as young as nine years were imprisoned for vagrancy.
In the 1960s the hanging of Ronald Ryan and the incarceration of unwilling Vietnam conscripts led to impassioned debate on capital punishment and prison conditions. Riots and mass disobedience by prisoners led to the 1972 Jenkinson Inquiry, which condemned the ill treatment of prisoners in the infamous 'H' Division. In 1987 five prisoners died in a fire in Jika Division. Early in the 1990s three new public prisons were opened, making Pentridge redundant. Pentridge closed in 1997 and almost 1000 prisoners were transferred to other prisons, public and private; the site was sold for redevelopment. After 150 years as an odious institution, Pentridge became a desirable residential address for those Coburg citizens who for so long sought its abolition.