Detention Block North Of Central Block, Hm Prison

The detention block north of the central block at H.M. Prison, also known as The Crescent, was built between 1832 and 1833 by Joseph Potter Jr. It was later altered and enlarged from 1861 to 1866 by R Griffiths. The structure is made of brick with ashlar dressings and features a slate roof. It is three stories high and has a symmetrical design with a concave facade and a gabled center. The building has modillioned brick eaves and a central entrance. Above the entrance, there are three round-headed windows with lintels that have enriched 'finial' keys and cast-iron casements. The central window features a segmental pediment dated 1864, while the windows for the cells were altered at a later date. The building also includes massive air shafts with panelled sides.