Behind the scarp revetments there are three long galleries incorporating casemated rooms for both musketry and carronades, all for the defence of the ditch. These are constructed mainly in brick laid to English bond, usually with axial semi-circular vaults of stretchers, invariably whitewashed. The east Musketry gallery consists of (in a southwards sequence) three musketry casemates, an expense magazine, three gun rooms for carronades, a single musketry casemate with steps up to the terreplein, another expense magazine, five musketry casemates, a well passage and nine musketry casemates. (location accurate to the nearest 1m based on available information)