This picture is in the Robert S. Peabody Museum of Archeology in Andover, MA (click here for their website) and a reproduction is sitting un-ceremoniously on the way out of the cafeteria at Philips Health Care - which now occupies the same location - the "bend in the river" archeological site reported on by Barbara Luedtke. The hill on the horizon, just to the right of the central pine tree in the picture and with a distinctive profile, is called Poplar Hill. I have visited it before [click here] and see it most mornings driving in to work.
I needed to go into work over the weekend and decided to take another walk at Poplar Hill afterwards. The hill is divided into two parts by a road:Last time I explored some of the hill to the right on the eastern side, so I thought it would be fun to explore the hill to the left on the western side. As you can see from the blue outlines, I found two new sites [and apparently changed my guess about the location of the small site on the eastern hill]. So I will report on the new sites.
Update: This erratic is on top of the western hill. Quite a landmark.