They appear as marks in the heather/grass and so could be natural or they could just be covered in soil and the underlying marking made of a substance on which the heather can't grow.
The nature of the valley they overlook, to me, indicates they could be the real thing. It is full of standing stones, ogham stones, stone circles and bullauns, as well as the largest hill fort in Europe. The figures actually overlook the hill fort!
They are on the west side of Keadeen Mountain in the Glen of Imail, county Wicklow - somewhere in the rectangle formed by (bottom right) grid ref S 940 890 and (top right) S 950 910. This area unforunately over laps on two OS maps (Discovery series 56 & 62)
My photo 2007
Many Thanks to Tom for the info
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