This is known as "Indian Cave," just north of where I live.
I hadn't been there since the pre-digital camera days (see: http://www.neara.org/macsween/cave.html & a similar to that http://wakinguponturtleisland.blogspot.com/2007/01/indian-cave.html &
I hadn't been there in years, so I went to look at it again.
There's a small remnant of a stone row along the stream:
Looking upstream, to the west, where the "cave" is located:
Some views of the "cave," the wall that might be a remnant of an enclosing that formed it into a "chamber," or a Stone Sweat Lodge:
The above matches this below:
Above: all those years ago, I never noticed neither the "v" shaped notch or the sort of rounded white quartzy "head" below it on an otherwise moss covered boulder...
Looking east at the cave, in the little canyon carved into the bedrock by this little stream (above) and then (below) two views each of a stone pile and a "single stone on stone with bucket," moving south and west to look for stone rows (which will appear soon as a new post).