Kate Middleton and Prince William Were Regular 'Alumni' on College Visit: 'It Felt Like Coming Home for Them'

Chris Jackson - WPA Pool/Getty Images Prince William and Kate Middleton

Kate Middleton and Prince William went back to where their relationship started — and spread the love!

The royal couple returned to the University of St. Andrews, where they met nearly 20 years ago, on Wednesday. They spent an hour with students in St. Salvator's quad, where the lawn had been decorated with large heart-shapes painted on the grass — and they took part in that most royal of traditions: planting a tree.

Principal and Vice-Chancellor Sally Mapstone, who chaperoned Kate and William during the visit, says, "They really listened. They were incredibly interested in this place, both because it means so much to them, but also because they want to know about student wellbeing after this terrible 15 months."

And one of the reasons they were able to connect with the young people they met was because it was clear "they have a brilliant relationship."

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Chris Jackson - WPA Pool/Getty Images Prince William and Kate Middleton

"You feel you are in the company of two people who are very happy with each other, know each other really well. That transfers over to how they interact with others," she tells PEOPLE. "They understand each other, they like each other and that communicates itself. It communicates itself and feels very natural — not in any way contrived — and that really helps people."

"Also they want to get to the heart of the matter," she adds. "So, they are not going to stand on ceremony but at the same time they also have those impeccable good manners that take you somewhere. It's not just about being chilled and relaxed, it's also about being very polite — and there is something to be learned from that."

ANDY BUCHANAN/POOL/AFP via Getty Images Prince William and Kate Middleton

The heart of the matter for the Duke and Duchess of Cambridge was talking with students about their wellbeing after a difficult year and a half when everyone's lives have been upended by COVID.

"They were asking about what the university had done for us, for our wellbeing," Joe Horsnell, 22, tells PEOPLE.

Adds Lorraine Callaghan, "They were asking about all the pertinent issues — straight into wellbeing and what the student experience was like for everyone. They were not aloof."

Chris Jackson - WPA Pool/Getty Images Prince William and Kate Middleton

The couple also teased each other over who used colored pencils more: the geography student, William, or the art history major, Kate.

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As they asked how Freshers' Week had been — normally a time of merriment and parties — it was inevitable that the tomfoolery and messy celebration that is Raisin Week (when students pelt each other with shaving foam) came up. The couple didn't pass on any of their secrets but there were "lots of wry smiles," says Horsnell, an international relations major. "They didn't let on anything!"

"They were here as alumni," adds Horsnell. "You could tell it felt like coming home for them."

Chris Jackson - WPA Pool/Getty Images Kate Middleton

With a spring in their step after a fun, active morning on the windy West Sands, they were animated and engaged as they talked to students about life in their alma mater — asking if they had taken part in the sport down on the beach.

Lottie Doherty, 22, art history and philosophy, says, "In the last year, with things being like they have, it has been great to be able to go for walks along the beach."

ANDY BUCHANAN/POOL/AFP via Getty Images Prince William and Kate Middleton

During the hour, they planted a silver birch with two students Deanna Coleman, 22, and Abi Whitefield, 25, to help publicize an initiative to offset the carbon created by students traveling to and from the college (many from the U.S.) by planting trees. The university is pledging to plant trees in the St. Andrews Forest so that over the next 600 years the use of carbon by transport can be neutralized.

"They were asking about how many trees there will be in the forest. I joked with Will that students won't be able to row across the Atlantic or cycle from China instead, and he said 'Why not?' They were both so down to earth," Coleman, an international relations student, says.

"They were so happy to be back in St. Andrews, and it's nice that we all have that connection with them," Whitefield adds. "They understood St. Andrews students and have the same mindset."

Chris Jackson - WPA Pool/Getty Images Prince William and Kate Middleton

The fact that William and Kate attended the college permeates a lot of current students' experience. Friends back home ask about it, and students gossip about "that was his [dorm] room or that was the flat they used to stay in," Whitefield, who's working towards a PhD in geography, says.

Coleman adds, "There is a raining of their presence here."

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At the couple's graduation, one of Mapstone's predecessors as principal made a speech about the high percentage of young people who meet and fall in love at St. Andrews.

"They mentioned that some of their best friends are also people who met and got together at St. Andrews," Mapstone adds. "That's just a well-established St. Andrews tradition."