I went back up hill from d, past the lowest road and the middle road. Then I found rock piles again. This collection consisted of a only a single little eyebrow of a pile with a weird standing stone:I failed to take a picture of the relation of this "pointer" to the first rock pile. It is behind us.
See how this rock comes out of the screen! You need 3D glasses. Somewhat more seriously, I imagine both the rock pile and this pointer (and perhaps the third rock) being involved together in obtaining useful shadows.
So that is it. This hill has many sites on it, probably several I did not see.