In the simplest of terms the concept of dry stone (or drystone) is to build a structure without the use of mortar or any other adhesive. Using basic physics, gravity, and some proven guidelines, almost anything can be built, and built to last, with stone.
Why build this way?
Rather than try and write this, it would be better to hear it from the wallers themselves. In 2017 our annual festival was held in Barriefield, Kingston, Ontario, at St. Marks Church. The event was documented in this video created by the Frontenac Heritage Foundation.