Map of sites on Bare Hill/Oak Hill - Littleton, Harvard, Boxboro, Bolton, Berlin

Rt 495 runs down from upper right. A bit of Rt 111 ("Mass Ave")  runs left right across the top of the map fragment. In red, the mound sites at the edge of the Hill (except the ones east of 495 are perhaps different). In blue are marker piles and other clusters. Larger outlines indicate areas with multiple clusters. The set of red dots makes a nice pattern along the edge of the hill, there should be other sites up there, if they aren't gone. I think there are still a couple of places I could look.
Update: taking a closer look at the map, maybe one place that would not be too hard to get to. But locked behind private houses, it isn't simple to sneak in. It is easier in Westminster.