Abbot-Reed-Powell - Inner Valley of Oak Hill, Harvard

The LFH showed me a way into this Harvard Conservation Land from the uphill, Bolton Rd side. First we passed some small "box" piles, little rectangles with hollows and quartz at the edge:

Another:

Another:

The same can be found on 'Codman Hill' at the end of Murray Ln in Harvard.

Then we got further downhill, to a big mound (lower left blue outline on map above) I have seen in the past [see here]. It is impressive:

A short closeup video:

As you get further away, you can see how big it is:

 See it filling the ravine?

Then we continued northeast, up the valley, towards the woods behind St. John's Lane. The mounds continued, slightly smaller, one after another along the southern facing slope of the valley. 

 From above:

Another:

Another view of the slope:

Another mound:

View again, note how there is a smaller part to the mound, on the right:

More, right up behind the houses (must be tresspassing):

Another:

Another with two part structure:

This also matches the "Lazy 9" style, mentioned here.

A nice collection of mounds. This valley is a real mortuary "complex". Should be on the National Historic Register. All the woods there are full of interesting structures. Walls of different ages and shapes: 

 Hun?