Prince William & Kate Participate In First 'Trooping The Colour' Celebration (PHOTOS)

Text By MEERA SELVA, Associated Press

LONDON - With his face half-hidden under a bearskin hat, Prince William rode through central London on horseback Saturday as part of his grandmother Queen Elizabeth II 's official birthday celebration.

The newlywed prince is taking part in the annual "Trooping the Colour," a procession held every year to mark the monarch's birthday.

His new bride Kate Middleton -- now officially the Duchess of Cambridge -- joined the royal family, riding in a horse-drawn carriage alongside William's younger brother Prince Harry , Camilla the Duchess of Cornwall and Prince Andrew, the Duke of York. She wore an ivory jacket and black hat, and had pulled a blanket with a tartan blanket over her knees to ward off the early summer chill.

The queen turned 85 in April, but the public party for the monarch's birthday is held on a Saturday in June when the weather is better. The custom dates from 1748.

William wore same red Irish Guards tunic with a blue sash that he wore at his April 29 wedding at Westminster Abbey and rose on a gray charger.

Take a look at photos -- including Catherine in a coat by McQueen -- and scroll down to keep reading.

Earlier on, the queen had awarded a set of honors on actors, sportsmen, academics, civil servants and members of the public who are judged to have made an exceptional contribution to society.

British actor Colin Firth, who won an Oscar for portraying the queen's father King George VI in "The King's Speech," was named a Commander of the British Empire or CBE in the Birthday Honors List .

Britain's honors are bestowed twice a year by the monarch -- at New Year's and on her official birthday in June -- but recipients are selected by committees of civil servants from nominations made by the government and the public.

In descending order, the honors are knighthoods, CBE, OBE and MBE -- Member of the Order of the British Empire. Knights are addressed as "sir" or "dame." Recipients of the other honors have no title but can put the letters after their names.

Most of the honors go to people who are not in the limelight, for services to their community or industry, but they also reward a sprinkling of famous faces. This year, 965 people will receive awards. Bank of England Gov. Mervyn King will receive an enhanced knighthood -- a Knight Grand Cross. Robert Edwards, who won a Nobel Prize in 2010 for his work on in-vitro fertilization, will also receive a knighthood.

Singer and songwriter Bryan Ferry was made a CBE while golfer Lee Westwood and cricket captain Andrew Strauss each receive an OBE or Order of the British Empire.

Artist Sam Taylor-Wood and jazz singer Claire Martin also received OBEs.