It was the Queen's official birthday, the pomp of Trooping the Colour was filling the air, Prince George was on the balcony at Buckingham Palace - and everybody's attention was focused on a hat.
In her first official engagement since giving birth to Princess Charlotte last month, what the Duchess of Cambridge was wearing was always going to attract attention.
But the disc-shaped Lock & Co head wear has put our local ladies into a spin - is it the next big thing in high fashion or should it be placed in a box at the back of the wardrobe, never to be worn again?
Northern Ireland milliner Marie Claire Ferguson complimented Kate's choice, saying the shape suited her well.
"The up-sweep at the back gives her height while not being overwhelming of her small frame," said the headwear expert.
"This hat makes a slight departure from her normal choice and is slightly larger in size.
"She tends to opt for a very classic, traditional look in her dresses and coats and in this case the larger shape and the mono colour of the hat complements the busy floral pattern on her Catherine Walker coat, which on its own, or with a more fussily trimmed hat, could make her look rather 'mumsy'."
However, Belfast Telegraph columnist Frances Burscough took a less symphathetic view.
"Whoever the royal milliner du jour currently is, I think they should have his or her head on a stake for these crimes of taste treason," she said.
"Kate looks like she's balancing a giant dinosaur egg on her head.
"Ideal if she's on her way to a Jurassic Park-themed fancy dress parade, or appearing in Puff the Magic Dragon panto at the Palladium, but not for joining the royals on a palace balcony for the formal trooping of the colour."
The Duke and Duchess of Cambridge were accompanied by George as he made his second public appearance at the Palace on Saturday. George wore a sky-blue shirt and shorts with matching shoes - the same outfit his father wore at the 1984 parade.
He was held by William and waved to the crowd below.
The one-year-old looked up at the aircraft as they roared over the Palace to conclude the pageantry of the ceremony.
The Queen wore a peach and silver dress and coat by Angela Kelly and a matching hat - previously seen at the Diamond Jubilee horse pageant in May 2012.
Yesterday, Kate looked far more comfortable as she donned casual blue jeans, a stripy Breton top and sunglasses to watch her husband play in a polo match. George was there again - dressed in navy shorts, a royal blue cardigan and a white shirt, the 23-month-old prince clutched a toy car at the side of the charity game in Tetbury, Gloucestershire. The Duchess held his hand as they walked around the edge of the field .
Prince Harry joined his brother the Duke of Cambridge in the competition, which was also watched by the Prince of Wales.
The Queen was also watching polo, dressed in pale pink, to present The Cartier Queen's Cup at Windsor Great Park, Berkshire.