Hello George,
We do not proceed on what is likely or 'would have been', we proceed on the evidence that is there. It would be very good to date the structure from its astronomy but at this early stage it has not been attempted. No archeology of any kind has been done at Trethevy, however so any date however putative, would at least be a date where at the moment there is none. We came in search of 'alignments' here ten years ago and found none, except perhaps the Feb/May alignment identified by Norman Lockyer in 1905, which seems to hold true. It is, however the pattern of light and shadow that the monument plays upon itself, both inside and out, that commands our attention. That's roughly it, although there is a wealth of evidence for other usages, not least the direct observation of the Solar disc.
We are preparing to shoot our documentary and will be on site most of the summer.
Dave Kane
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