'Trooping the color' in London for queen's official birthday

Members of Britain's Royal family from left, Camilla, the Duchess of Cornwall, Prince Charles, Princess Eugenie, Queen Elizabeth II, ba

The Red Arrows fly past as Britain's Royals watch from the balcony of Buckingham Palace, after the annual Trooping the Colour Ceremony

Kate, The Duchess of Cambridge, holds Princess Charlotte with Prince William at right and Prince George, foreground, on the balcony of

From left, Britain's Queen Elizabeth II, Prince Philip, the Duke of Edinburgh, Kate, The Duchess of Cambridge, Prince William and their

Troops parade for the annual Trooping the Colour Ceremony in London, Saturday, June 17, 2017. (AP Photo/Kirsty Wigglesworth)

Britain's Kate, the Duchess of Cambridge returns to Buckingham Palace, after attending the annual Trooping the Colour Ceremony in Londo

From left, Britain's Prince Charles, Queen Elizabeth II, Prince Philip, the Duke of Edinburgh appear on the balcony of Buckingham Palac

Britain's Camilla, The Duchess of Cornwall, left, and Kate, The Duchess of Cambridge return to Buckingham Palace, after attending the a

Britain's Kate, The Duchess of Cambridge, Prince William and their children Princess Charlotte and Prince George appear on the balcony

Britain's Queen Elizabeth II and Prince Philip, the Duke of Edinburgh return to Buckingham Palace in a carriage, after attending the an

Domhnall, the regimental mascot for the 1st Battalion Irish Guards, parades past the crowd during the annual Trooping the Colour Ceremo

From left, Britain's Queen Elizabeth II, Prince Philip, the Duke of Edinburgh, Kate, The Duchess of Cambridge, Prince William and their

LONDON (AP) — Queen Elizabeth II and senior royals have marked her official birthday in the annual Trooping the Color celebration.

The 91-year-old monarch was greeted Saturday by hundreds of well-wishers on a sunny day in the heart of ceremonial London. She rode with her husband Prince Philip in an open carriage in the procession along Horse Guards Parade.

Prince William and Prince Charles were on horseback. William's wife Kate and Charles' wife Camilla were in a carriage with Prince Harry.

The queen traditionally celebrates her official birthday in June when the weather can be balmy rather than in April, the month of her actual birth.

The day began on a somber note when Elizabeth and Philip observed a minute of silence in honor of the victims of the horrific London apartment tower fire.