Scotland during the Roman Empire centuries. The most enduring Roman legacy may be that created by Hadrian's Wall. Its line approximates the border between modern Scotland and England and it created a distinction between the northern third and southern two-thirds of the island of Great Britain that plays a part in modern political debate. This is probably coincidental however, as there is little to suggest its influence played an important role in the early Medieval period after the fall of Rome. The 9th Spanish Legion participated in the Roman invasion of Britain, suffering losses under Quintus Petillius Cerialis in the rebellion of Boudica of 61,
Architecture of Scotland Trimontium, and a continuous fortification between the Firth of Forth and the Firth of Clyde known as the Antonine Wall, built in the second century AD. Beyond Roman influence, there is evidence of wheelhouses and underground souterrains. After the departure of the Romans there were a series of nucleated hill forts, often utilising major geographical features, as at Dunadd and Dunbarton. Castles arrived in Scotland with the introduction of feudalism in the twelfth century. Initially these were wooden motte-and-bailey constructions, but many were replaced by stone castles with a high curtain wall. In the late Middle Ages new castles were