A knoll at the interchange between Rt 90 and Rt 495 and a good Senior Thesis

Looking back at pictures I took, I realize there were rock pile groups all the way around this little knoll, shown on the map. There is a little causeway you can follow in from Fruit Street and it leads directly to a good sized pile:

I walked counter clockwise. This was part of a sequence of rocks and piles:

I expect this points to something, perhaps on the horizon, or perhaps seasonally.
On the far side of the hill there was a larger boulder, with rock piles radiating out from it in four directions - except the lines intersected a few feet to the side of the boulder. Here are some pictures:

Looking out from the boulder; a couple of inconspicuous piles and a small rock:

From another direction:

And another:

The piles were not impressive but they were all over the place. Also walls. Here was a double wall:

A typical undisturbed woodland. Mapping this place carefully makes sense. It would be a great project for a student thesis.