Silbury Hill 180
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Silbury Hill

spiral path

I'm a fan of the "gut instinct" approach. On that basis I tend to agree with you that it never rose to a point, it just wouldn't have looked right that way. And I also understand the Statue of Liberty parallel – there's certainly an element of "look at this" about it. Although I suspect the subtext wasn't "Bring me your huddled masses" but was more like "Up Yours".

On the other hand, there are dangers in just looking. For instance, I'm just as deeply impressed as you by the effect that the Silbury game would have on strangers on the Ridgeway, but the impressiveness of that effect isn't a guarantee that it was deliberately created as part of a master plan. Eg. The linear position of Silbury was determined by the position of the earlier much lower versions, not by the views of it that we now see. So any deliberate creation of views to it (or from it) was restricted to controlling it's height.

I'm sure that was done (which is a big argument for it being originally flat topped – they stopped when it was just right). But WHICH view was the one they intended to create? There are a number of apparently significant views of it, and we're all fond of noticing them, including several where we note with relish that it's flat top is level with the horizon. But there could only have been one that was deliberate, or at most two if topography at the target locations happened to be fortuitous. The lie of the surrounding land wasn't in their control. The only control they had was the ultimate height of the hill.

My gut feeling from looking at it was that they wanted to create a "peeping effect", i.e. just visible or intervisible, but no more. On that basis, the views to/from both Avebury and the Ridgeway are the ones that look to be the possible target ones, and all the others just "happened". There's a bit of a clue to this – the peeping effect is perfect at Avebury (centre of South Circle) but it's rather too much on the Ridgeway. Had the thing been 4 feet lower the peeping on the Ridgeway would have been perfect, but it would have been invisible at Avebury. So, maybe, the height of Silbury is primarily Avebury-orientated, with the Ridgeway view being a secondary and imperfectly executed second target?

(One thing though, that totally fascinates me as a surveyor - did they work the height out in advance, or did they just build upwards until the views appeared, and then stop?)

As for why it's visible from so many other places, and aligns significantly with the horizon, I'd have to cite a rather mundane explanation – it's because it's high, and pure chance, respectively. Each instance "could" be deliberate, but all of them couldn't.

Yeah... I'd go along with all of that, and especially like the 'peeping effect' idea.

There's just one tiny fly in the ointment though when it comes to the number of places Silbury can be seen from - trees. Four and a half thousand years ago the area may have been far more wooded than it is today and that would probably have blocked out some modern views of Silbury.

There's an example of tree-blocking actually; about a quarter of a mile down the road from Winerbourne Monkton, heading into Avebury, Silbury is just visible through the trees in wintertime. Once the trees have their foliage you can't see it (though I've never actually stopped the car at that point in the summer and checked the view carefully). There maybe other places where Silbury is only visible when the trees are bare.