Have seen a rock pile behind this church when driving past on Newtown Rd. Decided to get out and take a picture. Actually a small site with four piles.
Both piles in the picture have a flat side. These sides are parallel but not at the same angle as the line drawn between the two piles. Something like this:Here is a closeup of the rear pile:The flat surface is quite clearly deliberate.
Here is one of the less visible piles:This view of the four shows the pile spacing, which is somewhat regular.What I call a "marker pile" site. For better or worse this is the most common type of site found around here.