The Waleses are looking to upsize from their modest Adelaide Cottage in the grounds of Windsor Castle and an insider says that they are considering a mansion which was the favourite of Edward Vll

Prince William and Kate with their children(Image: Getty Images)

Prince William and Kate are house hunting as they look to upsize to a grander royal residence and insiders reportedly say they have one favourite.

The Waleses moved to Adelaide Cottage three years ago and while it is comfortable for them in the grounds of Windsor Castle it was unlikely to be their long-term base. The four-bedroom pad is fairly modest by royal standards and it is understood that they have been quietly on the lookout for alternatives. Adelaide Cottage is a fraction of the size of the Wales family’s former full-time – a palatial apartment in Kensington Palace and they want a bigger place for kids George, Charlotte and Louis.

William and Kate are reportedly looking at Fort Belvedere(Image: High Level/REX/Shutterstock)

And it appears as though the favourite location is Fort Belvedere, a stunning gothic revival mansion in Windsor Great Park. Sources have told the Mail on Sunday that William and Kate could be looking at Fort Belvedere which was built in the 18th century and was the preferred home of Edward Vlll before he abdicated to marry Wallis Simpson.

It was renovated by Edward who put in a swimming pool, tennis court and stables and it is a huge property which has a long path to the entrance and even has a moat running around it.

William and Kate are understood to have considered the vacant Fort Belvedere previously before deciding on Adelaide Cottage.

At that point they are believed to have thought Adelaide Cottage was more suitable as it was closer to Queen Elizabeth and they also wanted to give their children a more down to earth start.

The Wales’ moved to Adelaide Cottage two years ago (Image: REX/Shutterstock)

But now the situation has moved on and the grade ll-listed property could be the answer. “They feel they have outgrown Adelaide Cottage and need somewhere more substantial,” a source told the outlet. “This is the perfect new home for them. It has a swimming pool and tennis court, and Charlotte loves playing tennis.”

Previously it has also been suggested that the Waleses could have a larger base through an annex building by Adelaide Cottage which would avoid them having to move.

“Nobody knows that there is quite a spacious red-brick annex building that’s not being used next door to Adelaide Cottage. It’s currently inhabitable and needs extensive renovation works if it were to be used,” a source told the Express.

“Discussions have been ongoing for a while about using the property as part of the overall cottage grounds, but it’s just about finding the right time to kick the project off.”