The discussion on this subject by Simon Banton, who I think works for English Heritage on Stonehenge, at the Winchester Weekend, was really interesting as well. A pity it was not recorded. Afterwards I discussed his views with him, comparing his take with that of Prof. Clive Ruggles, who is much more sceptical of some of the claimed predictive purposes of Stonehenge in relation to the movements of the Sun and Moon. Banton takes the view that the builders of these monuments understood quite a lot of astronomy, and has reasonable arguments to back this up.
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Supporting amateur astronomers since 1890