Reconstructed section of Hadrian's Wall, Vindolanda. A reconstruction of the turf wall with a wooden milecastle and gateway: The replicas were constructed in 1972/73 assisted by a large number of Gateshead school children, in order to assess the effort needed for the different forms of construction, and to show visitors how large the wall was when it was built. It is still a popular exhibit for visiting groups, especially children, despite controversy among archaeologists.
Trajan's successor Hadrian adopted a policy of maintaining rather than expanding the empire. Borders (fines) were marked, and the frontiers (limites) patrolled. The most heavily fortified borders were the most unstable. Hadrian's Wall, which separated the Roman world from what was perceived as an ever-present barbarian threat, is the primary surviving monument of this effort.