The Danish royal dropped in on the brewery to mark Northampton’s trade links with her country.
In 1974, she officially opened the Carlsberg brewery in Northampton – notable as the first outside of Denmark.
Benet Slay, chairman of Carlsberg, said that Princess Benedikte had been given a watch by the brewery when she opened it, and he was stunned to see that she still wore the same timepiece when she visited this time.
He told the BBC: "I was really amazed that the princess still had the watch and it still worked."
Mr Slay also talked about the tour that they had given the princess, saying: "We showed the princess Carlsberg beers in production and our new plans." During her visit, Princess Benedikte also saw the Northampton Alive project at the Guildhall.