During their 11-year marriage, the Prince and Princess of Wales have celebrated so many milestones. Last year, they marked their tenth wedding anniversary, while this year they celebrated their three children starting at Lambrook School as they moved into their new Windsor home.
WATCH: Kate Middleton says the sweetest thing about Prince William
They enrolled at the University of St Andrews in Scotland in September 2001 and became friends. The pair both lived at St Salvator's Hall residence, but it wasn't until the following year in 2002 that a spark grew. They were pictured publicly together for the first time in 2004 when Kate accompanied William on a family ski trip to Klosters in Switzerland.
During their dating years, the couple attended sports events, concerts and friends' weddings together, with Kate also present for some of William's biggest public moments, including his graduation from Sandhurst in 2006. While the couple rarely show public displays of affection, William was spotted kissing his girlfriend after playing in a match at Eton College in 2006.
It was a big moment for the couple when Kate and her parents, Carole and Michael Middleton, attended William's graduation from Sandhurst Military Academy in December 2006. While the Middletons were not publicly pictured with the royal family, they had prominent seats in the stands to watch the parade. It sparked rumours that an engagement between the pair was imminent, but royal fans had to wait four more years.
William and Kate are renowned for their love of sports, and the pair were animated as they cheered on England during the RBS Six Nations Championship match against Italy at Twickenham in February 2007. The pair were joined by William's younger brother, Prince Harry.
Who can forget when William and Kate rocked matching green tweed ensembles at Cheltenham Festival in 2007? The royal girlfriend wore a co-ordinating skirt suit by Katherine Hooker with Chanel sunglasses.
The couple briefly broke up in 2007, and William said of their split in their 2010 engagement interview: "We were both very young. It was at university, we were sort of both finding ourselves as such and being different characters and stuff, it was very much trying to find our own way and we were growing up." Kate added: "At the time, I wasn't very happy about it but actually it made me a stronger person," and she later said she "valued" that time for herself.
But the pair sparked rumours of a reconciliation when Kate attended the Concert for Diana at Wembley Stadium on 1 July 2007, on what would have been the late Princess of Wales's 46th birthday. She was seated two rows behind her future husband, as they sang along to the likes of Take That.
Four years after their first public picture, the couple enjoyed a skiing holiday in Klosters, Switzerland in March 2008. The couple have since enjoyed ski trips with their children.
A shy Kate was present for William's graduation ceremony at RAF Cranwell in April 2008. While William was dressed in his military uniform, his girlfriend opted for a white Reiss coat, which she has reworn on several occasions, including last year on the couple's tour of Ireland.
The Prince was spotted putting his arm around his girlfriend as the pair enjoyed a stroll after William played in a polo tournament in 2009. The Cambridges now take their children along to polo matches, with mum Kate chasing after her youngest son, Prince Louis, during a charity match in summer 2019.
Kate proudly watched as William graduated from RAF Shawbury in January 2010, where he was awarded his wings as a fully-fledged helicopter pilot. The Prince of Wales and the Duchess of Cornwall were also present at the ceremony.
William and Kate attended Harry Meade and Rosie Bradford's wedding in Gloucestershire in October 2010, shortly before they announced their own engagement. The future royal bride looked stunning in a blue dress by Issa - strikingly similar to the style she would wear for her engagement photocall.
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