Kate Middleton will perform her first royal duty since the birth of Prince George on Anglesey on Friday.
The new mum will join her husband Prince William to open the three-day marathon that sees runners circumnavigate the Welsh island.
Kate was not initially expected to attend the event but nearly five weeks after the birth of her first child, the diligent royal is clearly eager to get back to work.
They will leave their baby son George safely tucked up at home while they meet competitors and event organisers.
The Duke of Cambridge will then officially start the gruelling 135-mile ultra marathon.
After winning fashion fans worldwide with her impeccable maternity wardrobe, Kate’s style watchers will be eagerly awaiting the outfit she chooses for the event.
The tough race follows the Anglesey Coastal Path around the island which William and Kate have called home since 2009.
It is also the place where their one-month-old son Prince George has spent the last couple of weeks since travelling there with his mother from his grandparents’ house in Berkshire.
Since being back on Anglesey, Kate has been getting back into the swing of relaxed island life. She was spotted stocking up on food at a supermarket in Anglesey on Monday.
Casually dressed in a striped jumper, black leggings and flat shoes, with her hair pulled back into a ponytail, the 31-year-old pushed her trolley around the aisles picking up supplies for herself, her husband and their baby boy.
Their public appearance at the race launch will most likely be one of their last on the island, before William finishes his tour of duty there in September.
When he opened the Anglesey show on 15 August, William spoke of his love for the island and its residents.
“I know that I speak for Catherine when I say I have never in my life known somewhere as beautiful and as welcoming as Anglesey. The views across the Menai straits are undoubtedly among the most stunning in the British Isles.
“I know that both of us will miss it terribly when my search and rescue tour of duty comes to an end next month and we have to move elsewhere.
“From the bottom of my heart, thank you for making my wife and me so welcome when we arrived here, as you do thousands of visitors each year.
“This island had been our first home together, and it will always be an immensely special place for us both.
“Catherine and I look forward to returning again and again over the coming years with our family.”