The Queen's coffin will be carried during the procession to Westminster Abbey on a 123-year-old gun carriage towed by 98 Royal Navy sailors in a tradition dating back to the funeral of Queen Victoria.
On the day of Victoria's funeral in 1901, her coffin was to be carried on the gun carriage through the streets of Windsor but in the bitter cold of that February day, the horses which were going to pull it panicked and reared up, threatening to topple the coffin off the carriage.
Captain Prince Louis of Battenberg - the future First Sea Lord of the Royal Navy - intervened and suggested to the new monarch, Edward VII, that the senior service should step in.
Once this was agreed, the horses were unharnessed and improvised ropes were attached to the gun carriage, which weighs 3000kg, and the team of sailors was brought in to ensure the coffin was carried safely for the rest of the route.
Only nine years later, at the funeral of Edward VII, the new routine became enshrined as a tradition which has been followed at all state funerals since including those of Kings George V and VI, Sir Winston Churchill and Lord Louis Mountbatten - the son of Captain Prince Louis of Battenberg.
Nowadays, it is kept under environmentally-controlled conditions at a temperature of between 16 and 20C and at humidity of between 40 and 70 per cent to prevent it becoming dry and brittle and to stop fungal growth.
It was built at the Royal Gun Factory at the Royal Arsenal in Woolwich to carry the standard light field gun of the Army at the time, the breech loaded 12-Pounder, but was converted into a ceremonial gun carriage by fitting a catafalque - a raised platform with horizontal rollers for moving the coffin.
The gun carriage is stored at HMS Excellent on Whale Island in Portsmouth where its upkeep is the responsibility of custodian Lieutenant Commander Paul "Ronnie" Barker.
He told the PA news agency: "The gun carriage lives in an environmentally-controlled room in HMS Excellent so we try to keep it at a constant temperature and weekly I go in and turn the wheels a quarter turn to stop them from going egg-shaped with gravity and lots and lots of polishing.
"In preparation for this event we have increased that polishing 10-fold - if you look at the gun carriage, the barrel itself hasn't been chromed, that's years and years of polishing and lots and lots of elbow grease.
"I tend to get upset if I see a new scratch so I have probably crawled over every single part of it in the past four or five years."
He added: "I will feel immensely proud on the day, it's something that has been prepared for many, many years for this occasion and it's a great honour to be part of the backroom crew, knowing the gun carriage is going to perform to the highest standard along with the sailors who are going to pull the Queen on her final journey."
Stephen Prince, head of the Naval Historical Branch, who has been advising the funeral planners, said the navy planners had been keen to follow the traditions of state funerals.
He added: "We advise on what has been done before, not necessarily as a constraint completely but just so we know where we are starting from, so it's not an immobile process, but you want to have a good sense of where you come from."
Mr Prince said that the Queen was closely tied to the navy, adding: "It would be really hard to come up with anybody having closer links with the Royal Navy because the Queen is the daughter of a naval officer and she's married to a naval officer and two of her sons then serve as naval officers.
"So quite apart from the inevitability of the monarchy there is such a strong family connection."
At the funeral, the gun carriage will be pulled by a 98-strong team of sailors known as the Sovereign's Guard, while 40 sailors march behind the carriage to act as a brake.
Maintenance is carried out on behalf of King's Troop Royal Horse Artillery based in Woolwich, with work on the wheel and coach carried out by Mike Rowland and Son Wheelwrights and Coachbuilders from Colton, South Devon.
The carriage was last fully overhauled and refurbished in 1985 with the next major overhaul anticipated to take place shortly after the funeral.