Royals

Watch: Changing of the Guard at Buckingham Palace for Prince William's 40th

The ceremony is considered to be the peak of regimental discipline and ceremonial excellence.

A Changing of the Guard ceremony has taken place at Buckingham Palace to mark Prince William's 40th birthday.

Considered the epitome of ceremonial excellence and regimental discipline, troops from the Irish Guards marched to Buckingham Palace past a large crowd of spectators.

The Duke of Cambridge, celebrating his birthday on Tuesday, is Colonel-in-Chief of the Irish Guards.

Supported by military musicians, the crowd were treated to a number of songs – including Sweet Caroline.

Also at Buckingham Palace for the ceremony was 10 Queen's Own Gurkha Logistic Regiment, supported by the Band of the Brigade of Gurkhas.