Royal Citadel Great Store

The Royal Citadel Great Store is a storehouse, later used as barracks, now serving as a store and offices. It was built between 1667 and 1675 for the Board of Ordnance, and converted to barracks in 1844. The building is constructed of Plymouth limestone rubble with granite drip courses and parapet coping. It originally had two parallel roofs with a central valley, but these were replaced with a single deep slate roof with coped gables and plain parapets. Rendered stacks rise above the cross walls.

The building has a large double-depth plan, originally featuring a central entrance. A single-storey carriage house was added to the left side. The exterior is three storeys with a six-window range on the first floor, plus a central blocked former loading hatch now fitted with a clock. A wide central doorway, constructed of C16 granite with carved spandrels and a square hoodmould, is now blocked, as are the windows above it (the uppermost opening through the parapet). Later doorways, probably inserted around 1844, flank the left and right sides. Other openings are spanned by rendered brick arches and fitted with late 19th or early 20th century horned sash windows. Extensive alterations to the front wall are visible, while the other walls are rendered.

Inside, stair halls on the left and right contain C1844 cantilevered granite staircases with wrought-iron balustrades. Sections of C17 timber framing remain, visible behind later 20th-century linings on the spine wall.

This was a significant Ordnance Board warehouse, one of the country's key defensive points, and is larger than comparable stores at the Morice Ordnance Wharf in Plymouth. Its conversion to barracks represents a common form of military accommodation in England before the late 18th century. The building is a rare survival of an early military structure, associated with the Royal Citadel, an exceptional example of a C17 fort designed by Sir Bernard de Gomme.