Chapel Bay Fort

Chapel Bay Fort comprises a series of structures built primarily in the late 19th and early 20th centuries, forming a coastal defense battery. Three gun emplacements facing north towards the Haven are dated to 1903 and were designed for 6-inch Breech Loading (BL) guns. A single emplacement facing west is the sole remaining element of the original battery constructed around 1890, intended for 10-inch Rifled Muzzle Loading (RML) guns. One of the original guns survives and is currently displayed at West Angle Bay. The gun emplacements are characterized by concrete parapets with forward-sloping aprons that merge into the ground. Detonator stores are located beneath the guns, and although their doors are missing, the shell hoist mechanisms remain intact. Concrete stairs lead from a sunken communicating passage at the rear to the north emplacements.

At the rear of the communicating passage lies a sunken barracks unit containing eight segmentally brick-vaulted rooms, each approximately 5 meters by 6 meters, connected by a row of doors. Within seven of the barracks, hammock hooks are spaced roughly 40 centimeters apart along two sides. The last barracks room to the east appears to have been designated for officers, as it lacks these hooks. The barracks were originally heated by fireplaces situated back-to-back in alternate cross walls, each with a short brick chimney, now blocked up. Door and window frames were constructed to the soffit of the vaults, but all windows and doors have been removed. Above the barracks unit is the battery commander's station and a range-finding post. A cross passage within the unit provides access from front to rear, while another descends steeply to lower levels. Behind the barracks unit is a sunken passage featuring two ramps leading to ground level.

At ground level behind the barracks unit are several single-story buildings, including a workshop incorporating a generator and a smithy, a telephone room, the master gunner's office, and stores for oil and paint. An RA workshop, ablution room, and cookhouse are also present. The cookhouse is an early example of unreinforced concrete construction, protected by a cement render that is now damaged. The remaining buildings are constructed of brick. They are topped by flat concrete roofs supported on rolled iron joists. To the east of this row are the master gunner's quarters with a porch, and further rearwards are latrines. Closer to a bridge are additional latrines, a machine gun shed, an artillery store, a lamp room, and a coal store.

The fort is protected on three sides by a deep, defensive ditch flanked by concrete retaining walls. Two caponiers are accessible via tunnels from within the fort. Associated with Chapel Bay Fort are several ancillary structures located to the east, extending to the next headland. These include a 12-pounder quick-firing battery and a minewatcher's post at grid reference SM 8596 0363, a well and pumphouse at SM 8610 0355, and a submarine mining establishment with an engine room, generator room, store, and test room constructed from mass concrete at SM 8617 0351. Further features include Maxim gun emplacements, light emplacements, and a slipway.