The southern entrance (also known as Archcliffe Gate) to the western heights fortress was constructed in the 1860’s as part of a major revision of the southern defences. It was located at a point where the South Military Road attained the crest of the ridge. Included within the southern entrance defences were a series of gun rooms and a musketry gallery, which were accessed via a long, dog leg passage leading from the north western side of the gatehouse. The whole South entrance was demolished in 1967. (location accurate to the nearest 1m based on available information)