Great Chesters fort (AESICA)
Great Chesters is unusual in that it is largely unconsolidated and remains an atmospheric ruin, rather than a manicured monument. Covering 1.35ha (3.36 acres), this fort is (rather unusually) aligned east to west. It was added to the Wall some time after AD 128 and was the base for the cohortes VI Nerviorum and VI Raetorum respectively during the 2nd century, and cohors II Asturum and the Raeti Gaesati during the 3rd. The Notitia Dignitatum records the cohors I Asturum as being here later.
To the west, it has an unusually strong series of four ditches, presumably the whim of an officer with nothing better to do, since the land to the east and south is not similarly provisioned. In the north-west corner, the inner face of a corner tower is prominent, although the outer wall has fallen away. As with other such sites, the fort became a later farming settlement.
Inside the fort, surrounded by a wooden railing, there is part of the vaulted strong room of the headquarters building. From here we can look down towards the remains of the barrack buildings in the south-west quadrant of the fort, barely visible on the ground but very clear from the air. To the south can be seen the southern gateway, where there is a Roman altar which usually holds a few modern coins left on top in its focus by bemused visitors. The west gateway demonstrates the use of blocking walls (which, as we now know, were usually removed by later excavators at other forts), with first one then both portals ultimately being blocked.
Great Chesters is also remarkable for its aqueduct, the course of which is known for most of its length of 9.5km (from a source just over 4km away). It has been traced as an open channel, rather than an elevated structure. Sadly, there is nothing to see at the fort to mark its arrival. Most forts probably had aqueducts (Housesteads is an exception to this rule) but very few have been studied.