Dry stone walls are an iconic feature of the North York Moors.
It is difficult to imagine the landscape without them. It's estimated that there are over 2'000 kms of them in the national park.
Not all of them in tip-top condition but most of them are well maintained.
The greatest influence on the landscape of the Moors came during the 12th and 13th centuries when sheep farming evolved.
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 movment of sheep and cows.
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 6 metres of wall 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 maintanance...
