Hmp Perth, Tower Board Room

The complex includes a crescent-shaped Tudor style observation block, dating from 1839-42, which sits centrally between A and B Halls. The block is five and four storeys high and was designed by Thomas Brown. It features a prominent two-bay, five-storey central tower, flanked by lower, curved, crenelated four-storey blocks, which are in turn flanked by lower, single-bay, four-storey crenelated sections. The construction is of squared and coursed whinstone with cream sandstone ashlar margins and quoins, featuring chamfered openings with some incorporating hoodmoulds. Later replacement steel-framed multi-pane windows are located to the rear.

A Hall and B Hall, located to the left and right of the crescent block respectively, are imposing four-storey crenelated cell blocks constructed in cream ashlar. B Hall is slightly longer than A Hall, comprising 24 bays, although they are largely similar in design. Both have advanced, taller two-bay inner corner sections with machicolation. Later, slightly advanced outer bays were added in 1876 – three bays to A Hall and four bays to B Hall. Prominent crenelated ventilation chimneys are centrally positioned on both halls. Openings include some segmental and round-headed examples, particularly in the inner and outer bays, but most are regularly-spaced small rectangular openings with chamfered margins. Replacement timber multi-pane windows are present.

The interior of A and B Halls, viewed partially in 2014, follows a corridor plan with four floors of regularly spaced cells opening off either side of the corridor. The design is simple and functional, with few architectural features. The basement of A Hall, now unused for prisoner accommodation, retains some early, narrow, two-panel timber cell doors, featuring an observation hole and a central rectangular letter-box type opening. Surviving sets of vertical metal bars forming barriers, without the central gate, are also present. These appear to conform to Brown's designs and likely date from work around 1852-9.

In front of the Crescent Block stands a two-storey, five-bay, flat-roofed building with a crenelated parapet, now known as the Tower Board Room. Initially constructed by Robert Reid in 1810-12, it originally included a tall observation tower, now believed to have been demolished in the 1960s. Thomas Brown extensively altered the building between 1839 and 1842, converting it into the Governors’ Office and a reception centre for new inmates. It is built in squared and coursed whinstone with cream ashlar margins and quoins and features a two-way forestair providing access to the central first-floor entrance.