When I saw the first photo in Peter's post "Short stretches of wall - Gates Pond Rd Berlin, MA... , I thought about how I often find what I think of as "End Stones,", sometimes near water, at the end of many Linear Stone Rows that I think maybe of Native American origin. The one below is close to my house, as it looked before road reconstruction destroyed the point where the zigzag stone row met the linear row. The large end stone is by an intermittent stream along an ancient glacial lake shore on a large floodplain...
Above, before the reconstruction, looking west from the lake shore; below, looking north.
Up along the east branch that flows into the main river, near a waterfall, there are more linear stones rows that terminate in "End Stones."
East of Upper Falls, also a property line, looking south:
Upper Falls, North of E. Branch, looking north:
Lower Falls, South of E. Branch, looking south:
Back down to the floodplain, a stone row that changes from zigzag to linear, terminates in a large "End Stone," but this one has a rather testudinate stone on top of the boulder.
Ten miles away, to the north, near the largest remaining glacial lake in the state, the pattern appears along a roadside above the eastern shore: