An open spot in the woods

When there is no underbrush under the pine trees you think it is the trees dripping their bitter resin into the soil and killing things off. In a natural setting, there ought to be something under the trees - blueberries, or lillies of the valley, or some kind of underbrush. I was at one place in the woods this weekend in a space that was twenty yards wide and forty long where there were no pine trees and no underbrush either. It was not a bald spot, just a place where only grass and moss were growing. In places like that you get a feeling that a lot of people have walked there and tamped down ("compactified") the soil and I created a whole fantasy about this spot in the woods.

First off, I was walking along with minor knolls and level spots, along the side of a wet breakout zone. I saw one rock pile, exactly on top of a knoll, looking out but not much more. Than I saw the first of several circular trenches of varying depths: a foot or two deep.
In this picture the outline is perhaps 35 feet across. I looked at it and tried make sure it was real and tried to imagine why there would be such a thing here. In some places the trench was a little deeper than others - the right hand side in this picture. Then I saw another:
Again, some parts of the outline are deeper than others. In both cases, the "mound" inside the trench is little above ground level and suggests rather a bit of the dirt from the trench being tossed up. But what could be the purpose of such an outline? I was thinking it might be a longhouse or a wigwam outline - but of course I have no idea what that would look like. Finally, this spot was nestled just east of a steep little hill. Later I found a third outline and tried to get it on video (I'll put this in a separate post).

I climbed to the hilltop and then down the western side. Just a few feet down, actually not more than 60 yards from the outlines, was a level bare spot with grass and moss. On each side, facing each other across the space were remnant rock piles.
The bare spot seemed naturally to be a place where people could gather or -at least- walk around enough to tamp down the soil. So that is the fantasy. Three circular outlines for dwelling places and a level spot for dancing. It might be fun to excavate a place like this.