Interesting shot. Looks like the center stone fell, until it wedged in place lower down, then a lesser quality wall was built below and around it. And that wall has a little hill of dirt/sand slanted across the bottom. Maybe at one time someone didn't want that wedge shaped stone to fall any further? But they weren't the original builders. You can see where there was something, like a iron/steel beam(?), that went across all three of those upper stones. Maybe the removal of the beam caused the center stones to spread and the center one to drop. Nothing like that laying in the rubble, that I can make out. Must have been removed and taken away. The three doorways with stairs on the middle right indicate it had at least three floors. Do they seem to be hiding something behind the canvas that is set up on the right? Cool picture.