Richy - the circle of protective stones is around the grave of the murderer. They are in the ground and only stick up oout of the ground a tad bit in that Southwest Corner.
That place is by far the creepiest place i have ever been. Especially in that corner. We (Gina and I) saw some really fredaky stuff there. My batteries died 3 times there in my camera, and my headlight in my car even flipping burnt out! It was fine when we got there too.
Here are some of the photos I took.
This is the original
This is enhanced
It was not humid out, no mist visible to the naked eye, no smoking nothing. Here is a shot enhanced before the I took the one above.