All eyes have been on the Princess of Wales' style ever since she emerged in the royal spotlight as Prince William's love interest in the early 2000s.
Kate, who was once a twenty-something student rocking fun and flirty outfits, flitting between London nights out in glitzy mini dresses and sequin-adorned bodysuits, soon became royalty's best-dressed woman. Out with the old, clubbing outfits and flared jeans and in with the new era of Kate Middleton.
The royal, who tied the knot with the Prince of Wales in 2011, swapped out her ab-baring crop tops and low-slung skirts for smart tailored suits, glamorous pleated dresses and silhouette-skimming gowns that have now become synonymous with her unmistakable elegance.
Princess of Wales' best fashion moments
Royal fashion throwback
In 2004, Prince William's wife-to-be had no official royal-style rules to abide by. As the summer sunshine brought clear skies to Oxfordshire, a cool and collected Kate embraced the temperatures in a tweed mini skirt elevated with a chunky woven belt.
The beaming Princess rocked a tweed mini skirt and knee-high boots
The Princess' country chic aesthetic was in aid of a game fair at Blenheim Palace, where she was seen manning a clothing stall for 'Really Wild' clothing with a friend.
The Princess of Wales was seen wearing a 'Wild Thing' t-shirt
It was also where the royal was seen wearing one of her most memorable Y2K style moments to date, showing off her wild side in a baby tee emblazoned with the words 'Wild Thing'.
The royal-to-be finished off her look with a pair of tinted, rimless sunglasses and several boho bangles, letting her bouncy brunette locks fall to her shoulders in natural curls.
The Princess showed off her 'wild side' rocking a low slung mini skirt and baby tee
The air has been filled with nostalgia recently in light of the Prince and Princess of Wales' latest appearance, in which Kate was seen wearing a ring believed to have been given to her by her university beau during their first flush of romance.
Princess Kate's sapphire engagement ring is estimated to be worth £390k
It's possible that the ring was a gift from William, who previously gave his wife a diamond eternity band, or a "promise ring" worth an estimated £1.5k from their early relationship.
Maxwell Stone from Steven Stone explained: "During their university days, William gave Kate a promise ring, and though it’s hard to be certain, recent footage of the royal couple suggests she may be wearing this sentimental piece again. The ring is set on a rose gold Victorian band, featuring two garnets - Kate’s birthstone - and pearls to represent William’s June birthstone."