Established in 1851 and largely constructed in the period 1858 ? 64, Pentridge is the largest prison complex constructed in Victoria in the 19th century, and operated as the central establishment in the wider prison system from the early 1860s. Until its closure in 1996, Pentridge was Victoria?s central prison and the most well-known and used gaol in the State?s history. Most of Victoria?s convicted and notorious criminals were gaoled there between 1900 and the 1990s. In 1967, Ronald Ryan, who was convicted of the murder of a prison officer during an escape from Pentridge, became the last person in Victoria to be hanged at Pentridge.