Architecture of Scotland in the Roman era Elginhaugh fort, in Midlothian, dates to about this period, as may Castle Greg in West Lothian. The Romans eventually withdrew to a line in what is now northern England, building the fortification known as Hadrian's Wall from coast to coast. Around 141 CE the Romans undertook a reoccupation of southern Scotland, moving up to construct a new "limes" between the Firth of Forth and the Firth of Clyde. The resulting Antonine Wall is the largest Roman construction inside Scotland. It is a sward-covered wall made of turf, around high, with nineteen forts and extending for . The stone foundations and
Newcastle town wall town wall was constructed during the 13th and 14th centuries to repel Scottish invaders. Newcastle is about from the River Tweed, which marks the border between England and Scotland, as it did then. At that time there was a power struggle between England and Scotland, that eventually led to the Wars of Scottish Independence. The Scottish kings were always ready to take advantage of any weakness in the English rule to invade the North of England. An example of this is David I of Scotland, who took advantage of the civil war between Stephen and Matilda to invade Northumberland in