Ruthin Gaol was built in 1775 to the designs of architect Joseph Turner of Chester as a model prison. The building served as a county jail until 1866. When the Prison Act of 1865 was passed it was decided that the existing gaol would be extended and it was reported that it could hold around 100 prisoners. In 1878 Ruthin County Gaol became H.M. Prison Ruthin and it remained open for a further 38 years until 1916. In 1926 Denbighshire County Council bought the buildings from the Prison Commissioners and converted them for office and library use. In recent years the gaol has been adapted and refurbished as a visitor attraction and now houses the county records office for Denbighshire.