they were to guard against an attempt at reconquest by the Empire. This view, although widely disputed, has found recent support from archaeological evidence at Pevensey, which dates the fort's construction to the early 290s. Whatever their original purpose, it is virtually certain that in the late 4th century the forts and their garrisons were employed in operations against Frankish and Saxon pirates. Britain was abandoned by Rome in 410, with Armorica following soon after. The forts on both sides continued to be inhabited in the following centuries, and in Britain in particular several continued in use well into the Anglo-Saxon period. The forts In Britain The nine forts mentioned in the Notitia Dignitatum for Britain are listed here, from north to south, with their garrisons. Branodunum (Brancaster, Norfolk). One of the earliest forts, dated to the 230s. It was built to guard the Wash approaches and is of a typical rectangular castrum layout. It was garrisoned by the Equites Dalmatae Brandodunenses, although evidence exists suggesting that its original garrison was the cohors I Aquitanorum. Gariannonum (Burgh Castle, Norfolk). Established between 260 and the mid-270s to guard the River Yare (Gariannus Fluvius), it was garrisoned by the Equites Stablesiani Gariannoneses. Although there is some discussion as to whether this is actually the fort at Caister-on-Sea, and being on the opposite bank of the same estuary as Burgh Castle. Othona (Bradwell-on-Sea, Essex). Garrisoned by the Numerus Fortensium. Regulbium (Reculver, Kent). Together with Brancaster one of the earliest forts, built in the 210s to guard the Thames estuary, it is likewise a castrum. It was garrisoned by the cohors I Baetasiorum since the 3rd century. Rutupiae (Richborough, Kent), garrisoned by parts of the Legio II Augusta. Dubris (Dover Castle, Kent), garrisoned by the Milites Tungrecani. Portus Lemanis (Lympne, Kent), garrisoned by the Numerus Turnacensium. Anderitum (Pevensey Castle, East Sussex), garrisoned by the Numerus Abulcorum. Portus Adurni (Portchester Castle, Hampshire), garrisoned by a Numerus Exploratorum. There are a few other sites that clearly belonged to the system of the British branch of the Saxon Shore (the so-called "Wash-Solent limes"), although they are not included in the Notitia, such as the forts at Walton Castle, Suffolk, which has by now sunk into the sea due to erosion, and at Caister-on-Sea. In the south, Carisbrooke Castle on the Isle of Wight and Clausentum (Bitterne, in modern Southampton) are also regarded as westward extensions of the