Nearly 2,000 members of the Armed Forces will make a major contribution to the Queen's Platinum Jubilee celebrations this week.
Personnel from all three services will take part in events marking 70 years since the Queen's accession to the throne.
The Armed Forces' role in the celebrations is the twin result of hours of training for those involved and the centuries of tradition that dictate the ceremonial duties which form part of the jubilee programme.
Here's a detailed look at what military personnel are doing over the Platinum Jubilee weekend, from 2 June to 5 June.
What events are members of the Armed Forces taking part in?
The Queen's Birthday Parade – Thursday 2 June
About 1,500 soldiers and officers, 400 musicians and 250 horses from the Household Division of the British Army will take part in the traditional Trooping the Colour parade.
Meanwhile, 200 soldiers from the 1st Battalion Coldstream Guards will line The Mall.
A spectacular tradition for more than 260 years, Trooping the Colour marks the sovereign's official birthday.
Watch: Colonel’s Review: Prince William leads Trooping the Colour full dress rehearsal.
This year, the Irish Guards have the honour of trooping their colour before The Queen.
They will troop their new colour – a ceremonial flag carrying the regiment's battle honours – for the first time following its presentation by the Duke of Cambridge in May.
Following the COVID-19 pandemic, this year's Trooping the Colour will be the first since 2019.
Combining split-second precision with hours of focus, Trooping the Colour is a physically and mentally challenging undertaking for those involved.
It requires concentration, immense physical fitness, and stamina, with each soldier required to remember hundreds of words of command and complex choreographed movements.
Personnel will proceed from Buckingham Palace down The Mall and on to Horse Guards Parade, accompanied by members of the Royal Family.
The King's Troop Royal Horse Artillery will fire an 82-gun salute from Hyde Park in London, while the Honourable Artillery Company will fire a gun salute from the Tower of London.
Watch: Practice flypast for Platinum Jubilee held at RAF Cranwell.
Because the Queen's official birthday and Coronation Day coincide this year, there will be a double salute, with 124 rounds being fired from the Tower of London.
Gun salutes will also be fired across the country, including military bases and selected Royal Navy ships at sea at 2pm.
The Queen's Birthday Parade will conclude with a spectacular six-minute flypast over Buckingham Palace.
More than 70 aircraft from the Royal Navy, British Army and Royal Air Force will soar over the skies of central London, including the iconic Red Arrows, the historic Battle of Britain Memorial Flight and aircraft used by the UK Armed Forces on operations around the world.
Service of Thanksgiving - Friday 3 June
St Paul's Cathedral will host a service of thanksgiving for the Queen's 70 years of service.
More than 250 service personnel will form a guard of honour and line the entrances to the cathedral, while Armed Forces personnel from nations throughout the Commonwealth will line the cathedral's west steps.
The Royal Navy will be represented by sailors from ships HMS Queen Elizabeth and HMS Lancaster, which enjoy a special relationship with The Queen, The Duke of Lancaster.
The Band of Her Majesty's Royal Marines will provide music during the service inside the cathedral. They will be joined by four State Trumpeters of the Household Cavalry and nine Fanfare Trumpets of the Royal Air Force.
Platinum Party at the Palace – Saturday 4 June
More than 130 military musicians from all three services will provide live music by supporting a star lineup that includes the likes of Diana Ross and Sir Elton John during the Platinum Party at the Palace.
Platinum Jubilee Pageant – Sunday 5 June
Featuring well over 1,000 military personnel, the Platinum Jubilee Pageant will feature one of the largest tri-service musical ensembles ever assembled. The military spectacle will open the Pageant in Act 1, titled 'Queen & Country'.
The Pageant features marching detachments from Armed Forces regiments and units which have a special relationship with Her Majesty The Queen.
The Queen is Colonel-in-Chief of The Royal Scots Dragoon Guards, The Royal Tank Regiment, The Queen's Gurkha Engineers, The Royal Regiment of Scotland, The Royal Scots Dragoon Guards, The Adjutant General's Corps, The Royal Irish Regiment and The Royal Welsh.
The Queen is Captain General of both the Royal Regiment of the Artillery and Honourable Artillery Company, who will be marching as part of the Pageant.
Watch: Behind the scenes with the Household Cavalry.
Also forming a marching detachment are the Royal Lancers, known as Queen Elizabeth's Own Regiment, a title granted by Her Majesty in 2017 to reflect the long relationship between The Queen and Queen Elizabeth The Queen Mother, and the Lancers.
The Duke of Lancaster's Regiment, also marching, enjoy a special relationship with The Queen due to Her Majesty's position as the Duke of Lancaster.
The Queen is also Commodore-in-Chief of the RAF Regiment and Honorary Air Commodore of RAF Marham, who will form marching detachments from the RAF as part of a wider RAF group made up of 420 uniformed personnel.
In total, 770 British Army personnel will be on parade – a mammoth marching contingent made up of 200 mounted troops from the Household Cavalry and 570 musicians.
The Royal Navy will be represented by 200 service personnel split equally between the Royal Navy and Royal Marines.
Volunteers from the Maritime Reserves will make up around a third of the whole detachment.
Around the world – how deployed units will mark the jubilee
The Queen's Platinum Jubilee will also be marked by the thousands of UK Armed Forces personnel deployed worldwide on operations or exercises.
When their duties allow, personnel will celebrate the Jubilee on bases or ships in all four corners of the globe.
As celebrations proceed at home, around 12,000 sailors, soldiers and aviators, both regulars and reservists, will work on many vital tasks, including deterring Russian aggression, delivering aid, tackling drug smugglers, training allies, and fighting terrorism, according to the Ministry of Defence.