Queen Camilla and King Charles are marking their wedding anniversary today. The Queen opted for two outfits on the occasion – one for the civil wedding ceremony and another for the church blessing – yet it was Queen Camilla’s extravagant hats that truly captured the headlines at the time.

By tradition, royal women wear a tiara on their wedding day, regardless of whether they were born into royalty or married into it. However, Camilla chose two hats by her favourite designer Phillip Treacy instead for her momentous occasion. Louisa Rogers, a fashion expert, said that Camilla’s choice to wear a hat over a tiara “points to a conscious effort to play down the traditionally feminine and traditionally royal choice of headgear”.

“Millinery is closely associated with the aristocracy so it still holds its regal connotations without being seen as too ostentatious. It might have been judged as being in ‘better taste’ for this reason.

“The Phillip Treacy design itself is simple but avant-garde, in a muted beige tone that complemented the print on her longline coat.

“The feathers are lightweight and resemble wheat sheaves curving around the head – something Treacy described as ‘perfect and natural’. I would suggest that this choice of materials was also to make Camilla feel more approachable and down-to-earth as she had been villainised in the press since the affair had been common knowledge for some time.”

Fashion expert Karine Laudort added: “Queen Camilla has always been one to wear memorable hats, headpieces and fascinators over the years at various official celebrations such as Zara Tindall’s wedding, Christmas Card photos or even at Meghan and Harry’s royal wedding.”

Zoe Burke, editor of Hitched.co.uk, commented that Queen Camilla “got it exactly right”. She said: “It was never going to be easy to compete with Diana’s iconic wedding dress, so she went in the complete opposite direction, stayed true to her own style and created an understated bridal look that was both regal but also low-key.

“While she wasn’t typically bridal in her appearance, she did follow the royal tradition of having two wedding dresses – a modest knee-length dress in cream with a matching jacket and hat for her ceremony, before switching to a pale blue floor-length gown with embroidered coat and a very stylish headpiece for the blessing.

“The Queen finished her look with a gold and diamond-tipped bridal headpiece by Philip Treacy, which I took as her own personal way of saying, ‘I might not get to wear a tiara like the other royal brides, but see if I care’.”

Phillip Treacy said at the time: “It was a thrill to design a headdress for her because it was a momentous, historical moment for everybody concerned. The process [of making her wedding headdress] was simple because the she left the headdress to me, she put her trust in my ability. The inspiration was to draw, with feathers, something that encapsulated the spirit of the occasion.”