Royal Marine Barracks Archway Block

Guard house, officer's quarters and divisional offices, school, now chapel, including entrance block to the Royal Marine Barracks at Stonehouse. Built 1867–71 to designs by Colonel G Greene, Director of the Admiralty Works Department.

The building is constructed of Plymouth limestone ashlar with limestone dressings and dry slate roofs. The roofs of the main blocks are hipped to returns with dormer windows set behind stone parapets with moulded cornices. The taller central bays have pedimented fronts and rears with steep ramped pyramidal roofs to towers surmounted by weather vanes. Ashlar lateral and end stacks rise from the main blocks. The architectural style is Baroque Revival.

The plan consists of a double-depth central block with a central archway and chapel above it, connected by single-depth sections with rear arcades to double-depth outer accommodation cross-wings, the northern wing being deeper than the southern. The road front presents a two-storey carriageway block flanked by three-storey-plus-attic blocks, with two-storey pavilions and three-storey cross-wing end blocks. The left-hand block has a basement. A central pedimented block projects from the road front, displaying a finely carved coat of arms. An impost string links an arcade of five round arches with architraves, these spanning original hornless sashes with fanlight heads. Mid-floor strings and rusticated quoin strips provide horizontal and vertical articulation. The ground floor features channelled rustication surrounding small side arches and a large central round carriage arch. Above this arch, flanking ashlar masonry frames two round medallions carved with upper torsos. The flanking blocks have quoin strips at the breaks, plain stone architraves, and ground-floor pilastered openings with pedimented porches. The courtyard front is simpler in detail but remains the principal elevation, with three–five–three-bay flanking blocks incorporating square towers to the central bays. Two-storey linking sections of five bays have projecting round-arched open loggias to the ground floor. Three-bay pedimented end blocks project with central bays set under segmental pediments, linked to full-width triangular pediments behind. Each tower ramped inward to a narrower upper stage, with clock faces on each side and a swept pyramidal roof. The right-hand clock indicates wind direction. Most windows are original hornless sashes with glazing bars; the ground floor of the cross-wings has tripartite sashes flanking segmental arched doorways to the central bays.

The interior contains former apartments and offices fitted with six-panel doors and panelled shutters with plaster cornices; some stone fireplaces have been boxed in. A stone cantilevered open-well stair with iron stick balusters stands to the south of the through arch. The five-bay through arch features round-arched vaults with entrances on each side to offices and the guard house. Above this arch, the former school, now a chapel, has a shallow barrel vault with plaster decoration and late 19th-century fittings including an organ.

Originally the building housed the 1st and 2nd Commandant either side of the archway, with the first-floor schoolroom (now chapel) above. The northern end range accommodated 24 subalterns, while the office and pay office were located off the inner arcades. Greene was responsible for several important buildings in the royal dockyards, including the Sheerness boatstore. This block forms a strongly articulated and richly decorated range with contemporary additions to the north and south, extending westward and closing the 18th-century parade ground. Stonehouse represents the oldest and most important group of barracks in England not forming part of a fortification, a very rare example of 18th-century military planning and a complex of great historic value.