Rough Castle *
After the emperor Hadrian died in AD 138, the new emperor Antoninus Pius decided to occupy the lands north of Hadrian's Wall. He sent the legions north and established a new frontier on the narrow neck of land between the Clyde and the Forth. In the years following AD 142 the Antonine Wall was built running from Bo'ness to Old Kilpatrick.
Rough Castle was a relatively small fort. The defences were only ever built in earth and timber. The North Gate provided access north of the frontier and was well defended.
Along with the rest of the Antonine Wall, the site was abandoned around AD 162 (possibly even several years before) when the Romans withdrew to Hadrian's Wall.
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