Portland Castle

Portland Castle is a coastal fortification dating to approximately 1540, constructed as part of Henry VIII’s defensive network and costing £4964-19-10d at the time. It is built of Portland ashlar, with a lead and slate roof. The castle’s design comprises a circular keep that encloses an octagonal hall, flanked by wings set at an obtuse angle, and encompassing a gun platform at its upper level, all enclosed within a segmental wall facing the sea. A short, cranked passageway provides access to the octagonal hall from the west side. Large rectangular rooms are positioned on each side of the hall at both ground floor and upper levels; the ground-floor room to the southeast served as the former kitchen. The straight enclosing walls feature rectangular openings with splayed jambs, a weathered string course at mid-height, and a further string directly below a bold segmental parapet with wide, splayed gun ports, detailing that repeats around the upper level of the roofed quarters. The seaward segment sits upon a wide, splayed glacis and incorporates five segmental-headed, deeply double-splayed gun ports below the weathered string course, with further gun ports within the segmental parapet. The gun platform, situated behind the parapet and accessible via a walkway, is paved with stone flags.

Internally, the ground floor features stone flags, while the upper floor has timber boarding supported by substantial floor joists and beams, some of which are original. The walls are ashlar and unpainted. The octagonal hall is sub-divided at each level by timber and plaster partitions. The kitchen has very deep, splayed openings leading to former gun loops, with flat, straight-sided inner arches. The considerable thickness of the walls is evident in the depth of the reveals to all openings. Various arched fireplaces are present, along with stone staircases ascending to flat-slab stone ceilings.

Portland Castle was originally paired with Sandsfoot Castle in Weymouth, approximately three kilometers to the north across the harbor. Historically, the castle was surrounded by a moat. It was equipped with 13 guns in 1623, increasing to 21 guns by the time of the English Civil War. The castle was held by Royalist forces but surrendered in 1646. From 1816, it was occupied by the Manning family, and the adjacent Captain’s House was constructed. In 1870, the castle reverted to Crown ownership and, in 1984, became an English Heritage Property in Care.