Britain's Queen Elizabeth II Tuesday attended a thanksgiving service at St Paul's Cathedral to mark her 60-year reign, without her husband, Prince Philip, who is in hospital with a bladder infection, DPA reported.
The queen, 86, cut a lone figure as she climbed the steps of the cathedral for a service that has been described as the "spiritual finale" of the four-day celebrations.
Prince Philip, 90, was taken to hospital Monday, for the second time in six months. He suffered a heart scare at Christmas, when he had a coronary stent fitted.
Around 2,300 people filled the cathedral for the service, during which Prime Minister David Cameron was set to read a lesson.
After the service, and a lunch at Westminster Hall, senior members of the royal family will take part in a carriage procession through the heart of the British capital.
The procession, for which hundreds of thousands lined the route since early morning - and some even camped overnight - will be followed by a balcony appearance.
On Monday, veteran pop stars, including Paul McCartney, Stevie Wonder and Elton John, played at a concert for the monarch outside Buckingham Palace.