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's Wall probably planned before Hadrian's visit to Britain in AD 122. According to restored sandstone fragments found in Jarrow which date from 118 or 119, it was Hadrian's wish to keep "intact the empire", which had been imposed on him via "divine instruction". Although Hadrian's biographer wrote was the first to build a wall 80 miles long to separate the Romans from the barbarians", reasons for the construction of the wall vary, and no recording of an exact explanation survives. Theories have been presented by historians, mostly of an expression of Roman power and Hadrian's policy of defence before expansion. On