Looks like the nearby trees are mostly gone now and the site has been cleaned up to the point where it looks like a garden rockery.
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Clicked on the link and at first thought that it was a 'design feature' in the housing estate. At least they left it there I guess. Only thing similar over here that springs to min is this megalithomania.com/show/site/988/abbeyquarter_north_passage_tomb.htm with the Xtian cross and all.