Something that may help you on your quest, but probably not about the air-speed velocity of an unladen swallow, is on January 25 at Cardiff University's Centre for Lifelong Learning at 7.15pm.
Juliette Woodis is giving a lecture on "The Holy Grail in Wales".
By the way, I didn't get to this in the end. Does anybody know if I missed anything. I have to admit that the last time I went to one of her lectures it was difficult to hear her voice above the snoring (really).