Princess Diana, Kate Middleton, and Meghan Markle have all worn some of the most stunning royal blue dresses in fashion history. This countdown ranks the top 10 most beautiful blue gowns ever worn by a royal, from the engagement photocall that sold out a designer overnight to one of Diana's final public appearances before her death.

In this video:
10. Camilla's icy blue Bruce Oldfield gown at the No Time to Die premiere
9. Queen Maxima's cobalt Jan Taminiau gown at King Willem-Alexander's inauguration
8. Meghan Markle's Safiyaa cape dress at the Fiji state dinner
7. Kate Middleton's Elie Saab look at Royal Ascot
6. Meghan Markle's Victoria Beckham dress at the Endeavour Fund Awards
5. Kate Middleton's iconic Issa engagement dress
4. Kate Middleton's Jenny Packham gown at the German state banquet
3. Princess Diana's Catherine Walker gown at the Cannes Film Festival
2. Princess Diana's Versace gown in Sydney
1. Princess Diana's Jacques Azagury dress at Swan Lake

Which blue dress do you think deserves the top spot? Let us know in the comments below.

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