Harry left his wife and baby boy at home and was seen arriving at Windsor castle with his uncle and aunt, the Earl of Wessex and the Princess Royal, who was joined by her husband Vice Admiral Timothy Laurence.
The Duke of York arrived by car with his ex-wife Sarah, the Duchess of York, and their daughter Princess Beatrice and her boyfriend Edoardo Mapelli Mozzi.
Meanwhile, the Queen arrived a few minutes ahead of the bride with the Duke of Edinburgh, who was making a rare public appearance.
Philip appeared in good spirits and joked with the Dean of Windsor, the Right Reverend David Conner, who was waiting to greet the monarch and her consort.
The Queen wore a pink A-line coat, and a lilac and pink silk dress by Stewart Parvin, with a matching hat by Rachel Trevor-Morgan.