The queen was accompanied by only five members of her family -- her heir, Prince Charles and his wife, Camilla, Duchess of Cornwall, and Charles' sons, Prince William and Prince Harry, and William's wife, the Duchess of Cambridge -- The Daily Telegraph reported. The choice appeared to be a message that Charles will become king.
Thousands of people endured low temperatures and rain to cheer her.
"Oh, my goodness, how extraordinary," the queen exclaimed as she looked out on a huge crowd waving red, white and blue banners.
A message from Elizabeth to her people was also broadcast Tuesday. She recorded it Monday, shortly after her husband, Prince Philip, was hospitalized.
"The events that I have attended to mark my Diamond Jubilee have been a humbling experience," she said. "It has touched me deeply to see so many thousands of families, neighbors and friends celebrating together in such a happy atmosphere."
While Philip remained in the hospital, his youngest son, Edward, Earl of Wessex, said he was "feeling much better." Philip, who would have been at his wife's side, watched Tuesday's events on television.
The 86-year-old queen appeared strong and cheerful after a grueling weekend. Her great-great-grandmother, Queen Victoria, was unable at 78 to walk down the steps of St. Paul's Cathedral during her own Diamond Jubilee, but Elizabeth managed them with no sign of strain.
The thanksgiving service at St. Paul's was followed by lunch at Westminster Hall and a carriage procession to Buckingham Palace.