The Scots' Dike or dyke is a three and a half mile / 5.25 km long linear earthwork, constructed by the English and the Scots in the year 1552' to mark the division of the Debatable lands and thereby settle the exact boundary between the Kingdom of Scotland and the Kingdom of England. The Debatable Lands, also known as "Debatable ground", "Batable ground", or "Threpe" - Scots for something that is argued over - were in the West Marches, bounded on the west by the River Sark, to the east by the River Esk and Liddel Water, on the north by the Bruntshiell Moor and Tarras Moss, and on the south by the estuary of the Esk. The area was about ten miles from north to south and three and a half from east to west at its widest part.
These lands were finally divided between the English and Scottish Crowns by an agreement arbitrated by the French Ambassador. The physical border constructed came to be known as the "Scots' Dike", the "March Dike" or more recently the 'Scotsdike plantation'. The terminal points of the dike were marked by square stones bearing the royal arms of England and Scotland, however these markers have disappeared, possibly having been broken up for building nearby cottages. Spaced along the centre of the bank are a number of small unmarked boundary stones of uncertain date, some of which have fallen.