Interesting. Guess things like that are happening in a lot of places.
Where IS this? Your profile's location is rather broad.
Some of the New England states have many of these stone walls. I read that here in CT, where it is very rocky, early settlers piled rocks to form bordering walls like in the picture when clearing their lands for planting.
That photo looks just like the woods behind a house I had a long time ago, complete with old stone wall.