PEDANT ALERT
"Berwick to Carlisle is NOT the border, that border was the Roman one,"
Wrong Nut - the original Roman border was Hadrian's Wall from west of Carlisle to Wallsend along the N side of the Tyne Valley . Then for about 80 years it ran across the center of Scotland at the Roman turf Wall.
Berwick never featured on any Roman border
The current border was, and is, really a line along the high ground - for years it was a "debatable land" and kings of Scotland & England owned land on either side of the current line