More than 6,000 armed forces members will take part in King Charles’s coronation, which will make it the largest military ceremonial operation in 70 years.
Personnel from across the UK and the Commonwealth will join processions in London.
Thousands of veterans have also been invited to watch the coronation from a special viewing platform on 6 May.
They will join NHS workers on a stand in front of Buckingham Palace.
The guests, invited by the Royal British Legion, will be given a special view of the coronation, including the processions and flypast.
The first procession will be smaller in scale, and will feature just under 200 members of the armed forces who will travel down the Mall to Trafalgar Square, before turning onto Whitehall where they will march to Westminster Abbey.
Flanking them on either side will be over 1,000 personnel from the Army, navy and RAF who will line the route.
The biggest event of the day will be the coronation procession, featuring nearly 4,000 personnel, which will see the King make the historic journey from Westminster Abbey to Buckingham Palace.
Outside of London, gun salutes will be sounded from firing stations in 13 locations including Edinburgh, Cardiff and Belfast at the moment the King is crowned.
Prime Minister Rishi Sunak said he was incredibly proud of our military personnel who were “preparing to honour centuries of military tradition”.
He said: “As they stand shoulder-to-shoulder with our Commonwealth friends and allies, I know the hard work of thousands of our servicemen and women during the past weeks and months will culminate in an incredible display that will amaze crowds at home and across the world.”
Brit and Emmy-nominated composer Sarah Class has also been announced as the latest composer selected by the King to write music for the event.
Ms Class, who composed musical scores for Sir David Attenborough’s natural world programmes and National Geographic documentaries, said she was “very honoured and privileged and excited” to have been chosen.
She joins eleven other musicians selected by the King, as well as Andrew Lloyd Webber, who will compose the coronation anthem.
The King has opted for a shorter, smaller and more diverse ceremony than the previous coronation held for his mother, Queen Elizabeth II.
More than 29,000 personnel took part in the 1953 coronation, including 16,100 members of the army.
The King, who is the commander-in-chief of the armed forces, served in the Royal Air Force and the Royal Navy for a total of five years.