By Sophie Brown
BBC Sport at Aintree
Charles and Camilla also have a big weekend coming up
To those of superstitious leanings, it will have come as no surprise that the time of the Grand National has had to be put back to accommodate the royal wedding.
To them, it is all part of a four-year cycle of mishaps, which began in 1993 with the void race. In 1997, there was a bomb scare which forced a 48-hour delay while, in 2001, the course turned into a bog and only four horses finished.
With lashing rain threatening similar conditions on Saturday, not to
mention a Pope's funeral, a royal wedding and a local train strike set for Friday and Saturday, race officials will not be sleeping easily this week.
Most owners dream of having a horse running in the Grand National in their colours.
JP McManus, one of jump racing's leading owners, clearly enjoys the experience as this year's race will see no less than six running in the famous emerald green and orange hoops.
Since his first runner (who fell at the first fence) in 1982, the Irish multi-millionaire has had a second and a third from 12 runners.
He must be banking that he will finally break his National duck with what is a record number of entries for an owner.
Two British gold-medal-winning athletes from the Athens Paralympics will be taking part in a display of horsemanship at this year's Grand National meeting.
Pearson claimed three gold medals in Athens
Lee Pearson and Debbie Criddle, who both won individual and team equestrian golds, will perform a dressage display to music in front of the grandstands.
They will be onboard the horses on which they were successful in Athens - Pearson on Blue Circle Boy, nicknamed Gus, and Criddle on Figaro IX.
But after the heat of the Greek capital, conditions at Aintree - no sun and lots of cold wind and rain - could not be more different.
The idea that religion and gambling do not mix is not one entertained by a lot of Irish racing fans.
There was further proof of this earlier in the week when Irish bookmaker Paddy Power opened a book on who will be the next Pope and what name he will take.
For the record, Nigerian cardinal Francis Arinze is the current favourite at 11-4 while the next Pope's papal name is most likely to be John Paul, a 5-2 shot.