jimit,

Looks pretty well weathered to me, so that suggests it's not new. The website below shows a similar view, and also looks weathered:-

http://www.wychwood.gen.nz/travel/uk2/trails/avebury.htm

That's my twopenneth, but it'd be good to find an old black and white photo from, say, the 1920s.

All the best,
TE.