Hi Eternal - I'd love to be able to make a more informed comment about it, perhaps when I've visited the site next month I can contribute more. It's an interesting one though. You're probably right though - if it wasn't excavated or carved, maybe they didn't have the inclanation to put it in a foundation. My original point was that, having never been there, it just looked like a natural boulder (erratic?) I didn't realise it was part of an avenue. Do you think the avenue or alignment was built around it, or the otherway round?