>any particular reason why the path would be clockwise and not anticlockwise going up?<

I've based the hypothesis of a (clockwise) path on early illustrations (Stukeley* being the most important of course), and photos of the top of Silbury - some to be found at http://www.themodernantiquarian.com/site/30#images which seem to indicate that if a path existed at all that's the way it went.

>I'll look at the model when I've figured out how to, the message "This control contains an eDrawing2 file. The eDrawing ActiveX control cannot be used from a Netscape browser. Please use Microsoft Internet Explorer to view this model." really doesn't help as I'm using IE ....<

I'm afraid I can't help you much there Rune (perhaps Ishmael or someone else can); it took me a while to get it going but it's worth it.

* See also Stukeley's illustration of the Marlborough Mount in his <i>Itinerarium Curiosum</i> (the path he shows here has probably been re-cut but it may have followed an original).