Starting at Porto Town Hall, Prince Edward, 62, and Sophie, 61, received the highest honour when they were handed the keys to the city from the mayor, Pedro Duarte. Given in recognition of the special 640-year-old relationship between the UK and Portugal, the keys have only been awarded to nine people in the last five years, including French President Emmanual Macron (SP).

While the Duchess headed off for a private engagement, the Duke carried on his late father’s formidable legacy by meeting students taking part in the Duke of Edinburgh International Award at the Oporto British School.

With the chance to show off his knot-tying skills, help put the finishing touches on a tent and crack a few jokes about the perils of cooking onions during their treks, the Duke was on top form as he chatted to the participants.

With a huge cheer from the youngest members of the school, Edward wasted no time asking what their favourite subjects, hobbies and football teams were.

“Ice-skating” shouted one child, to which the Duke quipped: “Is there much ice-skating to do in Portugal?”

“No”, the youngster laughed.

Prince Edward and Sophie’s three-day visit saw them carry out engagements in both Lisbon and Porto, while also taking time to focus on issues important to them, such as youth opportunities and women, peace and security.

The Duke and Duchess of Edinburgh last visited Portugal together in May 2005, as The Earl and Countess of Wessex, and The Duke visited in June 2009.