Sean Adcock does a lot of field walling where he lives in Wales. He was explaining to me that Blaen y Nant, in the Llanberis Pass, below Snowdon the annual rainfall is 130inches and regularily has 40-50mph winds. The above photo shows where his main worksite has been for some time and the 2nd main propery in terms of amount of work done.
It is private land where he's been restoring many many meters of old field walls that mark property boundary. Most of the walls run along the transition from flatter field to land sloping down to streams. Walls are minimum of 5 feet including coping on low side, downhill side is usually around 6feet, tallest is about 9 feet.
Several good Canadian wallers have gone over there to improve their skills and to learn from Mr Adcock. People like Andre Lemieux, Kenny Davies, Akira Inman and Evan Oxland to name a few have worked on this particular site with Sean over the years ... There is a blog post back in April 29 if2013 . The first photo is Andre on downhill side of section they worked on when he visited and also a photo of him coping.
The google map photo shows what Sean has done at the Blaen y Nant property. The red walls are boundary, the orange wall is just under 5 feet on field side, and is mostly retaining(garden). This years work was the extension of the back garden wall beyond orange wall on the left hand side. The photo at the top of the page was taken about a third of the way along it from orange wall, looking down the valley towards Llanberis. Very Approxmately 40 linear metres and 800 square metres in total between other jobs over last 7 year.