Stonehenge is without doubt a magical place; I was there in 1972 when it was possible to walk right up to the stones and touch them. I was with a small group, but there were times when I could feel I was completely alone there and in touch with the spirit of the place.
I went again about 2002, and some of the magic had gone; there were hundreds of people, and no-one could get any closer to the actual stones than about 50ft. It was still magnificent though, and well worth a visit.
My wife Myranda and I were in southwest Ireland two or three years later, and we visited the Drombeg stone circle near Clonakilty, west of Cork; smaller than Stonehenge, but still magnificent, in a shallow coombe overlooking the open Atlantic Ocean. Myranda, who is very intuitive at times, suddenly felt the urge to play her bodhran (Irish hand drum) in the centre of the circle; after a minute or two of playing she said to me "Can you hear that?" Indeed I could; the stones were "singing" back to us, a wild high keening note, an overtone of the pitch of the drum itself - and suddenly I knew why the builders of Stonehenge had needed to transport those Bluestones all the way from the Preseli Mountains of South Wales, 200 kilometres away.
Preseli Bluestone is still quarried today, mostly to be made into jewellery; and the main quarry is close to a village called Maenclochog - the English translation would be something like "Stone that rings like a bell." The builders of Stonehenge wanted a particular kind of stone with special acoustic properties, that would resonate in a particular way to sounds that would be produced inside the circle - perhaps from drumming and/or chanting.
Recent research seems to have borne out this conjecture of mine. Our ancestors who built these ancient structures were no skin-wearing savages, as they have been depicted in countless books and magazine articles - and even English Heritage official publications; Not only were they astronomical technicians, capable of erecting 25-ton stones in astronomically precise alignments; they were also consummate acoustic engineers, who knew not only the exact kind of stone they wanted, but also where to find it.