http://www.themodernantiquarian.com/site/8389
I don't think Juamei, joolio, moey or I had no doubt these are ancient, & Margaret C didn't seem to doubt it.... Whether they're actual 'stone circles' or cairn-kerbs etc is less clear. I'd go for the latter & I suspect the others would to. Plenty of pix to give you a clue anyway.
Beautiful place on a nice day anyway!!!
love
Moth