Nigel, on 27 November 2006, 2:54, said:
Depends which ground you mean - the front of it is on the flood plain similar to Silbury -
http://www.themodern....com/post/33300
However, assuming your calcs are right - "13.73 meters tall, from its base, will do the trick" it looks rather short of that on the photo. Maybe 3 or 4 metres short?
Of course, we don't know if it had a wooden Viewing Platform of Doom or whatever on top

Nor do we know if a flat top is a deliberate flat top or a subsequently truncated flat top.
I can certainly find you 1.75 metres towards bridging the gap - the height from the ground to the observer's eyes. There is evidence they may have designed to such a tolerance. At one point in the Avebury South circle you can just see Silbury peeping over the intervening shoulder of Waden Hill (and vice versa of course). Bend your knees and its gone!
"Platform of Doom or whatever on top

"
Yes, I take responsibility for that one. I still like the idea of a tophouse for whatever purpose came to their mind -- and this would not necessarily have precluded a panoramic view, (aside from those timbers used in support). If they meant these things to embody mushrooms, (an idea I favor), the lines would have been continued, if not brought convex. Thinking comparatively: Pyramids are fairly common in ancient cultures. They have a cousin in the ziggurat -- are there any examples of bare-topped ones?
"Nor do we know if a flat top is a deliberate flat top or a subsequently truncated flat top."
True, but to what purpose? Egyptian pyramids were tombs, yet Silbury has yielded but one simple burial, (unfortunately lost to study).
"I can certainly find you 1.75 metres towards bridging the gap - the height from the ground to the observer's eyes."
An advantage in looking from Silbaby, but a disadvantage, for this effect, when looking from the Sanctuary -- (unless they felt the dead looked from there, lying down). However, if that's the case, I doubt the Sanctuary was more than a temporary mortuary... It's right on the Ridgeway, and the reek of rotting or burning flesh would become an issue.
"At one point in the Avebury South circle you can just see Silbury peeping over the intervening shoulder of Waden Hill (and vice versa of course). Bend your knees and its gone!"
Neat, but as Waden hill has been brought under cultivation, I expect it's lost something in height over the centuries.
"However, assuming your calcs are right - "13.73 meters tall, from its base, will do the trick" it looks rather short of that on the photo. Maybe 3 or 4 metres short?"
The best place I can to think of to look for corrections would be a core-based estimate of the actual height of S2, I took my figure from a highly schematic diagram --
a better reference is needed. The second consideration would be the roadfacing slope of Silbaby, which dumping may have masked. Does it have the same profile as the free slope, or is it steeper. How deep did the road cut into this hill? To be honest, on the OS map, it appears as if the crown of the hill was once, where the road currently is -- if there was an exact alignment. I'm curious about a sarsen I heard was on the top: (?) Is it alone? Is it at center?