It was not announced that the Duchess would be to make an appearence at the race in order to reduce the amount of crowds and press as the world eagerly awaits her return to the public eye after time spent at home with her new family.
Watch as The Duchess Of Cambridge makes her first post-birth appearance
Kate joined William at the Anglesey round the island marathon as the Royal fired the first gun shot to mark the start of the race, this having been Kate's first public appearence since the birth of baby son George.
Just so you know, we may receive a commission or other compensation from the links on this website - read why you should trust us