Wetland sloping site in northern Sudbury

I was studying the map of southern Concord and saw one place near Second Division brook where I had not been and thought it might be worth exploring. Over in south western Concord it is all sand and white pine trees, not good for finding rock piles, so driving along I was surprised to get to a slightly more rock area. I saw what looked like an interesting stretch of woods by the road and, uncommitted, decided to take a quick look. The further I got from the houses the more the woods continued, so I kept going until, hey! what is this?Stepping out of the car and walking up to a rock piles is always nice. As I walked around there were perhaps five or more low ground piles. Like this:
This pile, with the one larger rock, is more like a marker pile than a burial. This next one is more like a burial.
These piles were on a slight slope leading down to a wetland. A minor site, missing being in Concord by only a few yards. A most interesting feaure was a linear/elongated rock pile that was somewhat complex shaped, and not possible to photo. It was like a low ridge of cobbles:

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Blogger seems to get more and more unhappy the more pictures I add, until it stalls out. Cannot show you the linear arrangement here. OK I'll put it in the next post.