A site on Stow Rd. - from Journals, Dec. 2005

Then I went back to my car and was planning to go down through XXX center to the other side of YYY Hill. But instead I saw this out the car window to my left. I had seen this once before but hadn't been able to find it again. So this time I parked the car and got out to take a look.
It struck me that this is a pretty classic vertical faced pile. But other signs of a "marker pile site" were lacking.

Behind this one I spotted something large looming under the tree branches:
Before examing it, I photo'ed a nearby rock-on-rock group and also an uneven ridge of larger rocks and boulders.This is not a stone wall but a somewhat wiggly line leading from the road (in the background of the picture) down to the large pile. I imagined this line as a tail connecting to the head of the larger pile.
Here is another view of this larger pile. It is a classic "wall bulge" but without the wall. The pile itself has a well-built retaining wall. This is essentially identical to the piles at ZZZ Pond in Carlisle. You can see the pile contains rocks of all sizes but which have been carefully graded. The basic principles of field clearing are visible.

But then there are things like this nearby:Also one observes that the water starts at the big pile and then flows eastward a short ways into HHH Brook. Things like a stack in the water or this rather large rock-on-rock are not compatible with simple farming.

I also am struck by anomalies like this one in the wall there. The site is in a quadrant surrounded by stone walls. This is a view to the east (photo'd a couple of days later):
This seems like a reasonably good example of where the basic height of the wall is uniform and [as described in the previous post] one portion sticks noticeably above that height - a little symmetry with a window. It also looks like an example where the horizon is visible through the see-through hole.

Update: It is quite possible that farmers clearing fields might dump their cartloads onto an existing rock pile.