I had read and reacted to this poem before it was posted here and I would feel slightly uneasy about reusing any of the superlatives that I have already attached to it, but perhaps Persephone will forgive me if I just make one comment?
It is so uncommon to read any few lines that can drop you effectively back into the prehistoric moment, into the lives of the people that used and erected monuments, and for whom they must have been so vitally important. While the 'grey, haunted stone on the hill' type of reference can speak to our experience, Persephone looks behind and beyond that, to the possible minds of the movers of the stones.
Anyone wishing to open a gift with their eyes can link here:

http://www.thisisby.us/index.php/?sc=2&u=7235

*I can particularly recommend 'I Was Here', which concludes with the finest few phrases of new poetry that I have read in years.