Earlier research had suggested that the walls were from a fort built over the exising Vicus or Village, circa 160. then abandoned C. 196. More current research indicates that the fortifications are for the town alone, and that it was not a fort..
See: http://roman-britain.co.uk/places/bravonium.htm
Archaeological Report:
http://htt.herefordshire.gov.uk/docs/HA341_SHE19117_BRANOGENIUMLeintwardineCMPFINALVERSION.pdf