When was Hadrian's Wall built?
The Roman's were unable to complete the conquest of Britain due to those pesky Scotts. In 122 CE, Hadrian had enough of their nonsense and decided to build a wall to keep them out.
Two decades later (142 CE), the Romans began construction on the Antonine Wall, one-hundred miles further north of Hadrian's Wall. However, Roman occupation of the wall lasted less than a decade.