The Queen arrives at Buckingham Palace Coronation festival
11 July 2013 Last updated at 17:45 BST
For the first time ever hundreds of firms that supply goods to the Queen, the Duke of Edinburgh and Prince Charles are gathering at Buckingham Palace.
Royal Warrant holders from across the UK are holding a Coronation Festival with members of the public paying up to £90 to attend the event.
More than 48,000 are expected over the course of the festival, with 5000 expected to attend a gala in the palace gardens on Thursday evening.
Nicholas Witchell reports.