Since Neolithic times, herders of sheep and cattle have sought to construct sheep folds and cattle pens to defend their livestock against predators. They also wished to define the limits of their own fields. Planting thorn hedges and interweaving them worked to an extent - the Celtic Nervi tribe during the Roman period in what is now Belgium were experts at this - but in harsh weather a dry-stone wall is best.
The modern dry-stone wall still has its place in agriculture and in garden design and architecture, too. You can find walls like these all over the UK and in many countries including France, Germany and Sweden. Here you see multiple dry-stone walls in the Derbyshire Peak District, in this case acting as field boundaries for cattle. This is a very distinctive Derbyshire landscape.
The walls are constructed to a well-proven pattern. In the Derbyshire style of wall-building, a foundation is laid across what will become the base of the wall. Parallel walls are constructed on either side of the foundation, and these are wider at the base than at the top. At certain points, there are flat stones which stretch across the whole width of the wall, and sometimes the top few courses have three stones which form a horizontal ‘key’ and interlock. The centre of the wall is filled with small stones and rubble, so that rainwater can drain away. The National Stone Centre at Middleton by Wirksworth, on the edge of the Peak District in Derbyshire, contains many fine examples of dry-stone walling. Indeed, it is here that the Millenium Wall was constructed, in 19 sections, by members of the Dry Stone Walling Association. The Millenium Wall shows the many different styles and types of dry-stone wall built in Great Britain. The National Stone Centre also conducts workshops and holds courses in dry-stone wall construction.
Dry-stone walls need periodic attention, as frost can cause damage due to movement of the stones as the ice within expands and then thaws. However, the life of a well-maintained wall is almost indefinite. When I came to New England, I was pleased to see many dry-stone walls (some over 200 years old) being used as field boundaries. It was a cultural link between my old home and my new one.
As an aside, my favourite cartoonist, the late, great, Carl Giles once drew a magnificent cartoon of his fictional ‘Giles Family’ in Derbyshire, as part of his actual tour around Great Britain in a mobile studio. The family were depicted as becoming stuck in their caravan on a narrow Peak District road, in the midst of a maze of dry stone walls, and yes, I’ve seen that very thing happen!