Drystone

Drystone is a building technique in which walls, terraces, and other structures are built from stones without the use of mortar to bind them. Stability comes from careful stone selection, precise placement, and the weight and friction that develop between interlocked pieces. A typical drystone wall has a solid foundation, a rubble core, and a facing of suitably fitted stones. Through-stones, tie stones, and coping stones help lock sections together; many walls are built with a slight inward slope, or batter, to improve stability and drainage. Interior cores may be hearting, a layer of loose rubble that aids drainage and reduces weight.

Variations include random rubble drystone walls and more regular, coursed drystone construction. In addition to walls, the technique is used for terraces, field boundaries, shelters, and arches. Beehive huts and other small dry-stone structures are common in some regions and illustrate the versatility of the method.

Drystone construction is practiced worldwide, with notable traditions in the British Isles—such as the field walls of the Yorkshire Dales, Dartmoor, Cornwall, Scotland, and Ireland—as well as in Corsica, Sardinia, the Pyrenees, the Alps, and the Andes. The craft relies on skilled labor and long-standing knowledge of stone types, drainage, and plumb and level work.

Maintenance is key to longevity; without mortar, stones can shift over time due to frost, wind, or vegetation. Repairs involve carefully resetting displaced stones and, when needed, adding new capstones or tie stones to restore stability.