In true British style, guests of Princess Eugenie's wedding have arrived at the church donning headwear of all shapes, colours and sizes.
Spectators' eyes were peeled on the fashion choices as everyone from the Queen to Naomi Campbell arrived at St George's Chapel, to see Eugenie marry Jack Brooksbank.
Outfits ranged from the traditional to the outrageous - and many of the more wacky choices were in the guests' headwear.
Fergie's green and gold boater hat, which matched her emerald green dress, drew comparisons to the golden snitch from the Harry Potter series.
Model and singer Pixie Geldof made an entrance as one of the earlier celebrity guests to arrive, in a bright pink dress with a dramatic yellow fascinator.
Supermodel Naomi Campbell also made a grand entrance, donning a silvery-black outfit and a glamorous black fascinator to match.
On the less traditional side of things was English model and actress Cara Delevingne - who came wearing a tuxedo and tie, complete with a top hat.
She topped the look off with high heels.
Other picks were more kooky than classic - including one woman's hat which appeared to have two large bird's wings attached.
Sister Poppy Delevingne also turned heads with a risque dress which showed plenty of skin topped off with a large electric blue fascinator.
Meanwhile, Storm Callum made for a somewhat unwanted guest and posed a hazard to all hat-wearing attendees.
Winds were reportedly gusting at around 100km/h, making for an extremely windy Windsor day.
The gusts had guests holding onto their hats and fascinators on the way in to St George's Chapel. One heroic man was spotted running back up the hill in pursuit of his wife's headpiece.
Robbie Williams has already been blasted online after failing to help his mother-in-law retrieve her hat, after it fell off en-route to the chapel.
The singer was flanked by his wife Ayda Field and her mother Gwen Field - who's hat fell victim to the windy weather.
Williams stood idle, while Field took off after the navy piece.
While all eyes were on the coverage of Eugenie's big moment, some took the opportunity to cast their memory back to the Princess' choice of headwear for William and Kate's wedding.
Eugenie and her big sister Beatrice donned a pair of scene-stealing fascinators to Prince William and Kate Middleton's 2011 wedding.
Their hats were mocked by social media users, with Beatrice's choice likened to everything from a pretzel to a toilet seat.
Eugenie's pick was a bright blue ordeal with an arrangement of flowers and feathers perched on top.
But it seems that Beatrice and Eugenie can't win when it comes to public opinion, with Twitter disappointed the sisters hadn't worn equally extra headwear to Harry's wedding.
For her own wedding, Eugenie skipped the hats and fascinators all together, instead opting for a tiara borrowed from Queen Victoria.