The Duchess of Cambridge was all smiles today as she took part in the Garter Day celebrations.

Despite her heavy schedule of late, Catherine remained bright and fresh-faced as she showed off her third hat in as many days.

Waving from a carriage at Windsor Castle, the radiant newlywed wore a Philip Treacy head-piece, matched with a light blue-grey dress and matching coat.

Earlier, the Queen, Prince William and other members of the Royal Family took part in the annual Order of the Garter service.

The Garter Knights wore lavish blue velvet robes and black velvet hats with white plumes in a colourful spectacle that attracted hundreds to the ceremony held at St George's Chapel.