I was in a tiny dry stone walling museum a couple of days ago. It was interesting that they showed a bunch of techniques that were still highly specific to the region. Most of the walling was done with small slate-style rocks - very different from the Jura chalk I am used to, where we sometimes work with boulders a quarter the size of a car. They also showed a free-standing raised bed supported by dry stone, which I would love to have in my garden some day. We also came across these free-standing dry stone structures on our hikes in the region, something I've never seen around here.