The hundreds (thousands?) of sheep stells found in the Cheviots must be one of the most common structures to be seen on a walk. The are usually circular enclosures up to 30 feet across with a single entrance. Mostly made of stone, on occasions you will come across a ruined one built from turf. They are hardly used now, if at all, but when they were they would have fulfilled a variety of functions, acting as shelters and being places where a shepherd could manage sick stock or pen them for milking, lambing or marking.
The origins of the stell are unknown, although Roy’s eighteenth-century maps sometimes show circular structures that may have been instances of them. Built of drystone – without mortar – the walls of a stell are battered, which means they are angled on both sides and so are narrower at the top than the bottom.