It's believed there are over 5000 miles (8000 km) of dry stone walls in the Yorkshire Dales. Not all of them are in tip-top condition but most are well maintained.
One of the first questions any visitor asks is "why are they there"?
The very first dry stones walls were probably created centuries ago when early farmers were clearing the land for cultivation. Some walls are really thicker than might seem necessary, just because they were built in very stony areas. Most walls are built to mark field boundaries or mark land ownership, and limit movement by sheep and cows.
Tom Lord of Lower Winskill Farm, Langcliffe has over seven miles of dry-stone walls on his farm, some of which date back to the 13th century and are believed to have been built to deter wolves! When on a tour of his farm farm in Wensleydale, Adrian Thornton-Berry showed me some very straight walls rising up the hill near Swinithwaite and said they were built around 200 years ago by French prisoners of war taken from Napoleaon's army. Nearby are some large block foundations to a wall that dates back to the times of the Knights Templar. There's plenty of hidden history in those miles and miles of walls!
If you see very large stones being used as the base of the wall, that's often an indication of a wall that may date back to medieval times. Straight walls and fields that seem more uniform may date back from the Enclose period of the late 18th and early 19th century.
Dry stone walls are 'dry' because they are made without mortar, simply relying on their complex structure to stay up. They take time to build, rarely more than about 6 metres of wall in a day, which would use around 12 tonnes of stone - all lifted by hand! A good dry stone waller never picks up a piece of stone twice but is able to look at a pile of walling stone and pick up the right size and shape of stone every time. A well built wall should easily last for more than 100 years, with minimal maintenance.
The foundation course usually consists of larger stones, upon which two wall faces are built, forming a cavity which is filled will smaller stones. Walls are finished or capped with large stones laid at an angle or on edge. Through stones bind the two wall faces together. If you look at walls in different parts of the Dales, you'll notice small differences in their construction. If you compare the Dales dry stone walls to those in Devon and Cornwall and you'll notice a very different style.
You can see demonstrations of dry stone walling at agricultural shows through out the Dales during the Summer months, and learn more about thurles, batter and smoots, cripple holes, sheep creeps & throughs.