Tags: Prison.
HM Prison Onley is a Category C men’s prison operated by Her Majesty’s Prison Service. The prison is named after the lost village of Onley which is located next to the prison. Onley Prison is located in the county of Northamptonshire close to its border with Warwickshire in England. The prison lies in the parish of Barby in Northamptonshire. However the postal address of the prison is Willoughby Warwickshire therefore most sources list the prison as in Willoughby Warwickshire.