Queen Elizabeth II's granddaughter Zara Phillips is marrying England rugby star Mike Tindall in the country's second royal wedding of the year.
But the union of 30-year-old Philips, who is 13th in line to the throne but does not use a royal title, and Tindall, 32, will be a low key affair after the glamor of Prince William and Kate Middleton's April marriage.
Police warned well wishers gathering in central Edinburgh that there would be little to see, as the ceremony and the majority of the celebrations will take place in private.
The queen, William and Kate are all scheduled to attend, along with a host of British sports stars.
Tindall is a rugby player who has captained England, while Philips is a world class equestrian and likely to compete in the 2012 Olympics.