Hadrian ordered the construction of a massive wall across northern Britain beginning in 122 CE.
The wall marked a controlled frontier between the Roman province of Britannia and territories to the north. It ran roughly 73 Roman miles, or about 80 modern miles, from the Tyne near the North Sea to the Solway Firth. Construction involved forts, milecastles, turrets, roads, and substantial stonework in western sections.
Hadrian visited Britain in 122 CE during an inspection tour of the provinces. His frontier policy emphasized consolidation rather than unlimited expansion, and the wall formed part of a wider system of forts and roads. It was not an absolutely continuous barrier in every phase, nor did it permanently stop all movement.
Antoninus Pius later ordered another frontier structure farther north, the Antonine Wall, around 142 CE. Roman forces eventually returned to Hadrian’s Wall, which remained an important frontier installation until Roman authority withdrew from Britain.