Photos of Prince William and Kate living their best life at university

The Duke and Duchess of Cambridge are on a whirlwind tour of Scotland and one-stop that is sure to bring up fond memories is the place where they met 20 years ago – the University of St Andrews.

William and Kate, who headed back to their university on Wednesday to meet current students, lived a few doors apart from each other at halls of residence, St. Salvator's Hall, known as Sallies, in 2001.

The couple has returned to St Andrew's over the past two decades and earlier this week, the Duke spoke of his fondness for Scotland, saying that while he has painful memories of finding out about his mother's death during a family holiday in Balmoral, the country has also provided "great joy" for him.

"Alongside this painful memory is one of great joy because it was here in Scotland 20 years ago this year that I first met Catherine," said William. "Needless to say the town where you meet your future wife holds a very special place in your heart. George, Charlotte and Louis already know how dear Scotland is to both of us and they are starting to build their own happy memories here too."

Living in the same halls, William and Kate quickly became pals in their first year but it wasn't until spring of 2002 that the royal began to see Kate as possibly more than a friend. The moment that caught his attention was when the pretty brunette strutted her stuff in a threadbare black dress for a charity fashion show.

William paid £200 for a front-row seat and is said to have turned to his friend and whispered, "Wow, Kate's hot!" when it was her turn to walk the runway at St. Andrews Bay Hotel.

"It was the end of their first year," the couple's friend Ben Duncan told E! News. "She was in a very daring dress, in a sheer stocking-like dress. He was sitting front row and his eyes were like stalks."

Designer Charlotte Todd, who spent £30 to make the silk dress, went on to sell the iconic number for £78,000 at a Kerry Taylor auction, despite previously saying that she wouldn't put it up for sale. The mystery bidder was rumoured to be from Jersey. Charlotte also launched her fashion career on the eve of William and Kate's 2011 wedding.

The future King arrives for his first day of university life in September 2001, dressed casually in jeans, a shirt and a blue jumper.

It was Kate who is credited with convincing William not to drop out of university in the first year when he was struggling to adjust and persuading him to change his course from History of Art to Geography.

Surfing was another great love for Prince Charles' eldest son. Here a wetsuit-clad William is pictured walking the shoreline with a couple of friends in his final year of university.

Pictured in the main library, geography student William studies in his final year at university.

Kate graduated from the University of St Andrews with a 2:1 in History of Art in June 2005. The future Duchess, who was happily dating Prince William and had even joined him on a ski holiday in Klosters the year before, was pictured ahead of her graduation ceremony with her dad Michael Middleton.

Cheers and applause as Miss Middleton graduated.

William's graduation ceremony took place a few days before, with crowds gathering to see the royal, who got a 2:1, in his formal gown. Prince Charles and Camilla travelled up to Scotland to attend the ceremony in June 2005.

The Middletons also shared this sweet throwback photo of William and Kate as graduates ahead of their royal wedding in 2011. And the rest, as they say, is history!