Why this wall was built is now a mystery as it runs from the river along the valley bottom and up the hill through the woods. It is broken down where a path passes through it. I can only think that it is either an old boundary wall or it marked field edges before the woods grew up. Many species have colonized it and it is becoming quite overgrown and is gradually becoming absorbed by the woods.
Could it be that an old railway track ran this way? I have been watching a programme about abandoned railway lines and the guy walked a path with similar walls to this. I've just googled this and there is an old station in Clipstone. Lovely picture by the way, green & pleasant.
@pattyblue The wall is in Pleasley Vale not Clipstone but thanks for the suggestion. In fact there is an old railway line in the Vale but it runs about half a mile away from this part of the Vale. The old track is quite well mapped on Google Maps and I have seen in the local library railway maps with the line clearly marked.
@pattyblue & @peadar I have just found an online 6 inch OS map dated 1842 which covers this area and there is a line that delineates a field from a plantation which looks like being the wall.