Banna

This western part of Hadrian's Wall was originally built using turf starting from 122AD. The stone fort was built some time after the wall, in the usual playing card shape, with gates to the east, west and south. It was 7.5 mi east from Camboglanna (Castlesteads) fort and 6.5 mi from Aesica (Great Chesters). The fort was occupied by Cohors I Aelia Dacorum and by other Roman auxiliaries from approximately 126AD to 400AD. The two-mile sector of Hadrian's Wall either side of Birdoswald is also of major interest. It is currently the only known sector of Hadrian's Wall in which the original turf wall was replaced, probably in the 130sAD, by a stone wall approximately further north, to line up…

Inside were built the usual stone buildings, a central headquarters building (principia), granaries (horrea), and barracks. Unusually for an auxiliary fort, it also included an exercise building (basilica exercitatoria), perhaps reflecting the difficulties of training soldiers in the exposed site in the north of England. Geophysical surveys detected vici (civilian settlements) of different characters on the eastern, western and northern sides of the fort. A bathhouse was also located in the valley of the River Irthing.