A salute fit for a king: 41-gun Royal Salute marks His Majesty King Charles' 77th birthday

The King's 77th birthday has been honoured with a ceremonial 41-gun Royal Salute, a long-standing military tradition that requires meticulous planning and preparation. 

At midday at Green Park, the King's Troop Royal Horse Artillery sounded the salute using six First World War-era 13-pounder field guns drawn by 71 horses. 

While 14 November marks the King's actual birthday, the public celebration - a grand military parade and ceremony known as Trooping the Colour - takes place in June in the better weather. 

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Shortly after 11am, the soldiers, horses, and guns of The King's Troop Royal Horse Artillery departed from their forward mounting base at Wellington Barracks. 

They proceeded along Birdcage Walk, passed the Queen Victoria Memorial, and continued up Constitution Hill to Hyde Park, before taking their positions in Green Park for the salute.

A historic tradition

The tradition of the gun salute dates back to the 15th century, when ships entering a foreign port would fire all their guns harmlessly out to sea to show they arrived without hostile intent. 

Today, a gun salute is a formal military honour and a sign of respect or welcome. 

While the 21-gun salute is the standard ceremonial honour for a head of state, an additional 20 rounds are added to mark significant royal occasions, including the King's birthday, accession to the throne or a coronation.

Similarly, such salutes are used for major state visits, as was the case when US President Donald Trump visited the UK in September.