The facility was mostly built in the period from 1937 to 1939 and was completed in 1940 when Norway was attacked and occupied by
Nazi Germany in
World War II. The prison was used to house
Grini Prison Camp. The prison mainly housed Norwegians who were in
political opposition during World War II. After the war it changed its name to
Ilebu prison and on 8 May 1945 became a camp for prisoners, held in
custody and judged
traitors from World War II. From 1951, Ila supervision unit was used for prisoners who were sentenced to
detention in addition to
prison punishment. From 1976 to 2000, the prison was called
Ila landsfengsel og sikringsanstalt. The prison has about 130 prisoners. Ila Detention and Security Prison changed its name in 2002. Ila was given a role as a detention institution for men in Norway, and changed its name in Norwegian to
Ila fengsel, forvarings- og sikringsanstalt, later
Ila fengsel og forvarigsanstalt. == Ila today ==