Roman Cumbria to Wallsend on the Tyne estuary, with additional military installations running down the Cumbrian coast from Bowness to Risehow, south of Maryport, in an integrated fashion (and with forts at Burrow Walls and Moresby that were perhaps not part of the system). Historians believe that the Turf Wall from the River Irthing to Bowness-on Solway was rebuilt in stone in two stages. The most easterly five miles were rebuilt at the time of Hadrian, with the remainder being rebuilt after 150 AD. However, this is open to dispute: it is uncertain whether the building works in the second half of
Hadrian restore order. In 122 Hadrian initiated the construction of a wall, "to separate Romans from barbarians".The idea that the wall was built in order to deal with an actual threat or its resurgence, however, is probable but nevertheless conjectural. A general desire to cease the Empire's extension may have been the determining motive. Reduction of defense costs may also have played a role, as the Wall deterred attacks on Roman territory at a lower cost than a massed border army, and controlled cross-border trade and immigration. A shrine was erected in York to Brittania as the divine personification of Britain;