The Anglo-Scottish border, or the English-Scottish border (known locally as simply The Border), is the official border and mark of entry between England and Scotland. It runs for 96 miles (154 km) between Marshall Meadows Bay on the east coast and the Solway Firth in the west. It is Scotland's only land border. England shares a longer border with Wales.
The Firth of Forth was the border between the Picto-Gaelic Kingdom of Alba and the Anglian Kingdom of Northumbria in the early 10th century. It became the first Anglo-Scottish border with the annexation of Northumbria by Anglo-Saxon England in the mid 10th century. Lothian was taken by the Scots at the Battle of Carham in 1018 and the River Tweed became the de facto Anglo-Scottish border. The Solway-Tweed line was legally established in 1237 by the Treaty of York between England and Scotland. It remains the border today, with the exception of the Debatable Lands, north of Carlisle, and a small area around Berwick-upon-Tweed, which was taken by England in 1482. It is thus one of the oldest extant borders in the world, although Berwick was not fully annexed into England until 1746.