Prince William, 35, and Kate Middleton, 36 - who is currently pregnant with their third child - kicked off their royal tour in Sweden before heading over to Norway.
As well as visiting the royal families of both countries, the royal couple met with Swedish ice hockey players, attended black tie dinners and spent time on the slopes with the Norwegian Ski Federation.
During one of the final activities on the royal tour, William revealed he has an allergy - but it’s not one to food, pollen, fur or dust.
Before returning home to London, England, the couple took a walk around a park in Oslo with Norway’s Queen Sonja, Crown Prince Haakon, Crown Princess Mette-Marit and their daughter Princess Ingrid Alexandra.
As they walked around the snow-covered park, William was asked by a royal fan if he’d take a selfie, reports Hello!
Royal follower Kristin Larsen, 46, was armed with her phone, ready to take a picture, when William answered: “I’m allergic to selfies.”
But in order to not let Kristen down, he suggested they pose for a traditional photo instead.
Kristen said: “I’m just so excited, this is amazing. I've been waiting here for hours and didn't think he would stop, I'm so glad he posed for a picture.”
Prince William isn’t the only royal to show aversion to selfies.
In the past, Prince Harry, 33, has complained about selfie culture.
When asked if he enjoyed taking pictures with fans, he said: “I hate selfies.
“Seriously, you need to get out of it [the habit].”
William and Kate’s visit to the Scandinavian countries also revealed another point of royal protocol.
Both Scandinavian countries are in the midst of winter, with temperatures currently -2C in Stockholm and -6C in Oslo, and Kate, who is currently pregnant with her third child, understandably wrapped up in an array of coats - including a £650 jacket by Kjus.
But even when the Duchess was pictured inside in the warm she chose not to remove her coat - and there’s a reason why.
According to OK! Kate’s decision to keep her coat on - even in the presence of the Norwegian royal family at their home - is part of strict royal fashion rules.