There are different styles of stone piles located in the Hi-Tor region. They also vary in size. The largest resemble huge mounds with very little evidence of stacking.
It is possible that these large mounds were originally well formed stacks that have been changed due to the effects of gravity, animals walking over them, and trees falling on them. I would guess that the interiors of these piles are still constructed of stacked stones.
Another type of stone pile is a stone pile connected to a large boulder. These are rare in this area. I think that the reason for this is that there are few large boulders in this area. The bed rock is shale, the only large stones are an occasional glacial erratic.
The most striking style of stone pile are the stacked stone piles. They can be further broken down into styles.
Some of these stacked stone piles are circular and they taper with the shape of the hill. They are taller on the uphill side of the pile and less defined on the lower end. This could be the result of gravity's pull or they may have been built this way. This type of pile is usually built on the side of a hill facing the sun. By tapering the design anything laid on top of the pile would get excellent exposure to the sun. This might have been done for agricultural reasons or it could be that bodies would be placed in the sun until the flesh was gone, then the bones of the dead would be buried in the cairn.
Some of the stacked stone piles are rectangular and connected to a circular stack at one end. These seem to be located at the crest of a hill.
The final style is a small cylinder. This type of stone pile would likely be a trail marker. They are often set in lines at even intervals. Like many of the stone piles, when you find one the next one will be found as far as you can see in line with the last one.