The Duke and Duchess of Cambridge will celebrated their tenth wedding anniversary on 29 April, but the couple have been together for over 18 years.
Prince William and Kate began dating while they were studying at the University of St Andrews and since their 2011 royal wedding, they've gone on to have three children, Prince George, Princess Charlotte and Prince Louis.
Kate has made her own mark on the royal family, highlighting the causes she's passionate about, including the Early Years, mental health and sport. She's become one of the most photographed women around the world and a renowned style icon, with the 'Kate effect' coined after her engagement to William.
Here are some of HELLO!'s favourite photos you may have forgotten about over the years, including before she became part of the Firm.
READ: 10 best photos of Prince William and Kate Middleton from their dating years
Kate carried out her first royal duty ahead of the royal wedding in February 2011. She and William launched the new Hereford Endeavour lifeboat in Anglesey, where they were living at the time. The future Duchess charmed the crowds during a walkabout and christened the boat with a bottle of champagne. William even quipped at the time during a speech: "I do the talking, she does the fun bit."
WATCH: William and Kate release touching family video to mark tenth anniversary
All eyes were on Kate when she attended the passing out parade when William graduated from Sandhurst in 2006. It was the first time the royal girlfriend had attended an official event and she was joined by her parents, Carole and Michael Middleton. Kate wore a stylish red coat for the occasion, matching the Queen in the same hue.
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Kate attended the wedding of Laura Parker Bowles (the Duchess of Cornwall's daughter), and Harry Lopes in Wiltshire in 2006.
MORE: 21 of the most iconic (and expensive) royal wedding dresses in history
Sporty Kate spent the summer in 2007 taking part in training sessions with the Sisterhood cross Channel rowing team. Since joining the royal family, we've seen the Duchess go head-to-head against her husband in sailing events.
MORE: The royal family's talents revealed - including Princess Eugenie, Kate Middleton, Prince George and Duchess of Cornwall
The Duchess of Cambridge is a huge tennis fan and has been patron of the All England Lawn and Tennis Association since 2016. But before taking her place in the front row of the royal box, Kate was a regular at the tennis tournament, attending with her close friend, Sophie Carter, in 2008.
MORE: 14 of Kate Middleton's funniest and most relatable reactions at Wimbledon
Kate had the time of her life when she organised a charity roller disco in Vauxhall, London in 2008. She donned a green sequin halter-neck top, yellow shorts and pink leg warmers for the 80s themed event and was joined by her younger sister, Pippa Middleton.
MORE: 7 times Kate Middleton and Prince William were so in sync
Then a royal girlfriend, Kate made a rare appearance at an official event, the Order of the Garter service, in 2008. As William took part in the ceremony, wearing the full ceremonial regalia, Kate stood chatting with her future brother-in-law, Prince Harry.
MORE: The jobs Kate Middleton, the Countess of Wessex and others had before joining the royal family
In 2009, Kate made a surprise appearance at the Tenacity Of The Tasman documentary film premiere at Odeon Leicester Square.
Shortly before their engagement, Kate was in the crowd with friends to cheer on Prince William during a polo match in 2010.
MORE: 7 times Kate Middleton and mum Carole proved they were mother-daughter goals
The newlyweds stepped out the day after their fairytale wedding in April 2011 and royal fans went crazy for Kate's high street outfit, consisting of a blue pleated Zara dress and LK Bennett wedges.
For her first race day as a royal at the Epsom Derby in 2011, Kate looked stunning in a white Joseph jacket and Reiss dress with her signature LK Bennett nude heels at the time.
The Cambridges went to Canada for their first major tour shortly after their wedding in 2011 and Kate nailed her overseas wardrobe from the start. She effortlessly disembarked from the plane in her LK Bennett nude pumps, wearing a navy blue lace dress by Canadian-born fashion designer, Erdem.
The royals got behind Team GB during the London 2012 Olympics and here's sporty Kate trying her hand at hockey. Sales of coral jeans spiked after this engagement!
Just hanging out! We love this picture of William and Kate when they had a go at abseiling through the rainforest on the island of Borneo during their Jubilee Tour of the Far East and South Pacific in 2012.
The Duchess and her first-born child, Prince George, were spotted having a sweet mother-son moment during the Cambridges' tour of Australia and New Zealand. The pair had a little dance as they joined a play group.
Kate's renowned for her signature blowdried locks but we loved it when she experimented with a grown-out fringe, shortly after returning to work after Princess Charlotte's birth in 2015.
This has become one of William and Kate's most iconic photos as they sat on the same bench in front of the Taj Mahal in India, in 2016, where the Duke's mother, Princess Diana, was pictured alone 24 years ago.
Remember when Kate went all Katniss Everdeen on us? The Duchess was in fits of giggles as she tried her hand at archery during an official visit to Bhutan in 2016.
We were pleased to see Kate looking so well after recovering from severe morning sickness during her third pregnancy with Prince Louis in 2017. The Duchess was photographed enjoying a dance with Paddington Bear at an event in London's Paddington Station.
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