Fort Grange

Fort Grange, built around 1860, is one of a series of forts and is nearly identical to Forts Brockhurst and Rowner. It is a six-sided, symmetrical polygonal fort that was once surrounded by two moats, although only part of the inner moat around the keep remains. The two outer lines form a very obtuse angle, where a caponier projects, featuring a series of rifle loops above three gun casemates that face the former moat. Ramps from a central position lead to the north-west and south-west shoulders, where caponiers overlook the flanks' moats. Small barrack ranges extend along the gorge lines, continuing as a high wall across the moat of the keep.

The main lines of the fort originally had a moat and an earthen rampart, supported at the rear by intact storage casemates. The top of the rampart included open gun emplacements and interior sunken vaulted expense magazines. The flanks are two-storeys high, with Haxo casemates above ground-level casemates. The circular keep, designed as a last resort, is surrounded by a moat and features gun loops and several rifle loops, some within small caponiers. The centre of the keep has a circular courtyard with a two-storeyed barrack elevation, and a roadway runs along the axis, crossing the moat (now partly filled) via drawbridges with round-arched portals. The high earthwork above the keep provided gun emplacements capable of firing across the parade. Many details of the fort remain, and the main structure is intact, although the earthworks have been reduced and much of the moat has been filled in.