I'm not sure what you are saying Nigel. The only interpretation boards I am aware of are over near the river Kennet on the way up to WKLB and over by the Adam & Eve Stones. I admit I don't wander about there much these days but travel through on a bus at least twice a week - from the top deck of a bus I have seen Avebury in the morning and as evening falls. Silbury always mysterious, always the centre of its landscape. Recently I've watched the master thatchers re-thatch the Red Lion. I feel as though Avebury belongs to me as much as to anyone but I couldn't tell you who built it or why. Perhaps the NT feel the same way.