Large Platform Cairn from Tyngsboro

This is the largest rock pile at a favorite site in Tyngsboro. First view from the front, slightly to the right:Here is a picture from the left:
Here is a view from the left rear:It is not obvious but this pile is not a perfect rectangular shape. The corner seen from the front right is a sharp corner but the corner seen from the front left is rounded. Something like this:
Anyway, it is quite a pile.