Organisers announced today that Ms Boyle, Rolf Harris and classical maestros Il Divo will be among acts performing in the Diamond Jubilee Pageant 'The World Comes to Windsor' from May 10-13.
Hosting will be Alan Titchmarsh, who will be joined by narrators Dame Helen and Martin Clunes, while it will be aired peak time on ITV in early June.
More than 25,000 people, including royals, will watch the pageant in the grounds of Windsor Castle.
The 90-minute theatrical show is the curtain-raiser for celebrations taking place across the UK to mark the Queen's 60-year reign.
International performers have started arriving for one of the biggest events to take place in Windsor
The pageant will feature 550 horses and 1,100 performers from 17 countries including the Cossacks from Russia, Inuits from Canada, Oklahoma cowboys and Huasos from Chile.
Some performers will also appear at The Royal Windsor Horse Show in the private grounds of Home Park from Wednesday, May 9 to Sunday, May 13.
Top Ten Articles