The Queen dropped in on a wedding at Manchester Town Hall, while touring the city as part of the Diamond Jubilee celebrations.
Along with the Duke of Edinburgh, the Queen met newlyweds John and Frances Canning who had booked the venue before the royal visit was announced.
The Monarch even posed for pictures with the couple.
The Cannings, from Prestwich, decided to go ahead with their wedding despite the Jubilee events.
The meeting came as the royals attended a lunch at Manchester Town Hall, hosted by the lord mayor.
Rebecca Townley, from Manchester, who had gone to see the Queen with friends, was among the crowd of well-wishers outside the town hall.
"It was really nice," she said. "People from all ages gathering to see her made me feel very patriotic.
"Then when the Queen and Prince Phillip waved and everyone cheered, again it was very lovely.
"Plus she was wearing pink which was an added bonus."
Earlier, The Queen visited Salford and officially opened the BBC's base in the MediaCityUK complex, where she presided over the start of the BBC Sport Relief Mile involving 600 participants.
The royal couple also opened Royal Manchester Children's Hospital, the Royal Eye Hospital, Saint Mary's Hospital and a new wing at the Royal Infirmary.
The visit was part of the Queen's tour of the UK to mark her Diamond Jubilee.