Kate Middleton (and Her Flower Hat!) Lights up Royal Ascot Alongside Prince William and the Queen

Kate Middleton and Prince William have arrived at one of the most anticipated events on their social calendar: Royal Ascot!

The royal couple joined Queen Elizabeth for the annual five-day horse race, which kicked off on Tuesday.

Princess Kate wore a cornflower blue dress with sheer sleeves by Elie Saab and a matching Philip Treacy hat with a flower detail as she and William joined Prince Charles and Camilla, Duchess of Cornwall for their carriage ride during the processional onto the racecourse, which is a short distance from Windsor Castle.

Blue seemed to be the color of choice for several of the royal women, with the Queen, Princess Beatrice, Princess Eugenie and Zara Tindall all wearing various shades. Kate even accessorized her look with blue topaz and diamond drop earrings by Kiki McDonough.

They royal parents of three were among the guests on the first day of the horse racing festival that the Queen, 93, attends every year with her family and friends.

The Queen, who wore a blue coat and matching flower hat by Angela Kelly, hosted King Willem-Alexander and Queen Maxima of the Netherlands in her lead carriage that processed onto the course. Prince Andrew completed the foursome.

Also joining the Queen were her granddaughters Princess Beatrice and Princess Eugenie, who were in the fourth carriage. The sisters shared the carriage with the Queen’s private secretary Edward Young and one of the Queen’s cousins Princess Alexandra. Eugenie’s husband of eight months, Jack Brooksbank, was not at the race.

On Monday, William and Kate stepped out for the grand Order of the Garter with the Queen and other senior members of the royal family at St. George’s Chapel at Windsor Castle.

In her welcoming remarks to racegoers in this year’s Royal Ascot program, the Queen calls the event “one of the sporting events that I have been fortunate to enjoy throughout my life.”

Signing it “Elizabeth R,” she adds that even though racing has been taking place there for more than 300 years, and “much has changed, the horses remain the stars, thrilling us with their beauty, brilliance and courage. The quality and the depth of competition at the Royal Meeting has also continued to prosper.”

She adds, “The best horses and jockeys from across the globe are increasingly drawn to Royal Ascot, and it is truly exciting to welcome competitors from overseas, as strong international competition always adds further interest and fascination.”

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Last year, Meghan Markle made her debut alongside husband Prince Harry. But she will not be attending this season as she’s on maternity leave after welcoming baby Archie last month.

The Duchess of Sussex made an appearance at Trooping the Colour earlier this month, however, as it’s a family occasion celebrating the Queen’s birthday.