More from Mill Pond Conservaton Land - Burlington, MA

I was walking along on the paths in the southern part of the conservation land and came to a place where the bank at the side of the road was one big disturbed rock pile:
There was a big "borrow" pit nearby with the sand or gravel removed, so it seemed completely natural to assume this path-side collection of cobbles was just discards from removing the sand and gravel. But I had a hard time squaring that practical use with some of the other features nearby going up the hillside.

What was this?
Since I had seen several examples of short stretches of stone wall coming down the sides of ridges a quarter mile away (overlooking the Mill Pond [click here]) the presumption might be that this is another such impractical feature. Here is the view from above:
Starting a few feet from the top of that short stretch was another short wall contouring the hill:
Walking along this wall and looking back downhill I saw several rock piles, all in bad shape:
The solitary quartz could be deliberate or random.
I could not tell what this place was;some kind of site.