Today is Tynwald Day on the Isle of Man, a national holiday that sees an open air parliament convene onTynwald Hill, next to St John's Chapel. The tradition is associated with the Midsummer celebrations, and possibly Manannán mac Lir, and goes back at least a thousand years, and is said to be the oldest parliament in continuous existence in the world. The Beeb are live-streaming the events of the day:
Come 4.30pm the video will start recapping highlights of the day, apparently, and I think you should be able to view the video wherever you are.
There's a brief description of the Tynwald Court from the 17th century here, and a nineteenth century description here. These versions might swallow up a lot of your computer if you don't have a very good internet connection, though, so be warned! Alternative options can be found here and here (pages 29-30 and 10-11 respectively).