Resurrexi posted a pic of HK's wedding here: http://catholicforum.fisheaters.com/index.php/topic,3442056.0.html
But I have found a text description, from T. H. White.
The cathedral of Carlion was booked for it, and no trouble was spared that a good time should be had by all. The pontifical nuptial high mass was celebrated by such a galaxy of cardinals and bishops and nuncios that there seemed to be no part of the immense church which was not teeming with violet and scarlet and incense and little boys ringing silver bells. Sometimes a boy would rush at a bishop and ring a bell at him. Sometimes a nuncio would pounce on a cardinal and cense him all over. It was like a battle of the flowers. Thousands of candles blazed before the gorgeous altars. In every direction the blunt, accustomed, holy fingers were spreading little tablecloths, or holding up books, or blessing each other thoroughly, or soaking each other with Holy Water, or reverently displaying God to the people. The music was heavenly, both Gregorian and Ambrosian, and the church was packed. There were monks and friars and abbots of every description, standing about in sandals among the knights, whose armour flashed by candlelight. There was even a Franciscan bishop, wearing grey, with a red hat. The copes and mitres were almost all of solid gold cloth crushed with diamonds, and there was such a putting of them on and taking of them off that the whole cathedral rustled. As for the Latin, it was talked at such a speed that the rafters rang with genitive plurals — and there was such a prelatical issuing of admonitions, exhortations and benedictions that it was a wonder the whole congregation did not go to heaven on the spot. Even the Pope, who was as keen as anybody that the thing should go with a swing, had kindly sent a number of indulgences for everybody he could think of.
Splendid. Though I'm sure HK could find a few things to improve even in this scenario.
(This excerpt is actually from the second book of The Once and Future King, called The Queen of Air and Darkness, and depicts the double wedding between King Pellinore and the daughter of the Queen of Flanders, and St. Toirdealbhach--not a real saint!--and Mother Morlan.)