Watching the Wall

Hadrian's Wall was begun around AD 122, after the emperor Hadrian visited Britain. His biography in the Historia Augusta says he built a wall eighty miles long to separate the Romans from the barbarians. It ran across northern England from Wallsend on the Tyne to Bowness on the Solway, with small fortlets called milecastles at every Roman mile, turrets between them, and larger forts added along its line. In front lay a deep ditch.

The peoples beyond it left no writing. What we know of them comes from Roman authors and from archaeology. Tacitus describes the Caledonians as red-haired and large-limbed; later writers speak of the Maeatae and, from the end of the third century, the Picts. Across nearly three centuries the northern tribes traded with the frontier, served in its armies, raided across it and were punished for it. The Wall was garrisoned until around AD 400, and long stretches of it still stand.