Dry Stone Walling is a peculiarly British (almost uniquely) technique of providing field boundaries from local materials.
No mortar is used, so the building technique must ensure good structure. Each hilly region of the UK has it's own style of walling based on the characteristics of the local stone, but the Cotswold style is the smartest because the yellow Cotswold stone provides for flatter, more symmetrical stones to work with.
I like this picture because it emphasises the shapes and texture of the capping stones whilst the eye is led into the distance with a touch of Cotswold scenery in the far background. Click here for the side-on view.
This is a great shot, being surrounde by dry stone walls I've tried to take something similar a few times but I've never been happy with the result, you've cracked it.