It promises to be a royal tour unlike any other – a poignant moment marking unprecedented times.
The Duke and Duchess of Cambridge will on Sunday board the Royal Train for the first time, setting off on a festive three-day journey to pay tribute to those who have gone "above and beyond" this year.
The couple will traverse the UK, travelling 1,250 miles as they take in stops in England, Scotland and Wales.
Along the way, they will highlight the impact of extraordinary public generosity during the coronavirus pandemic, showcasing charities such as NHS Together and meeting frontline workers, teachers, mental health professionals, care workers and schoolchildren.
They will also celebrate examples of community spirit by showcasing the arts, heritage and live performance sectors.
Kensington Palace said the Duke and the Duchess would "pass on sincere thanks and gratitude" on behalf of the nation to those who have made incredible sacrifices to keep others safe.
At various points during the journey, they will hear about the sacrifices made by teachers who have worked hard to keep schools open and the armies of volunteers who stepped up to organise much-needed foodbanks. At other stops, they will focus on the mental health of students and the loneliness suffered by so many during lockdown.
But while the tour will shine a light on the year's many difficult experiences, Kensington Palace hopes it will also provide a much-needed uplift and help boost morale.
The royals will enjoy live performances from choirs, orchestras and schoolchildren and there will be a sprinkling of festive cheer, with carols and maybe even a reindeer featuring along the way.
A Kensington Palace spokesman said: "The Duke and Duchess are very much looking forward to shining a spotlight on the incredible work that has been done across the country throughout this difficult year and to sharing their gratitude on behalf of the nation for all those supporting their local communities ahead of the Christmas holidays."
The Royal Train is usually only ever used by the Queen and the Prince of Wales. Consisting of nine carriages, it is the only private, non-commercial train service catering to one family still in operation in the UK.
The train is run on cooking oil, thanks to the Prince's passion for the environment, while the Queen is said to have described it as one of the few places she can relax in total privacy.
It has been a permanent fixture of regal life since the reign of Queen Victoria, who became the first British sovereign to climb aboard when she travelled from Slough, then the closest station to Windsor Castle, to Paddington in June 1842. In her journal, she described the 25-minute journey as "delightful".
The train has since undergone many incarnations. In 1977, to mark the Queen's Silver Jubilee, a single set of carriages, including two royal saloons, was formed for the first time and has remained in service ever since.
The locomotives are capable of speeds up to 125mph, but when on royal duty are restricted to 100mph due to the age of some of the carriages.
The Queen's saloon includes a formal entrance vestibule, a sitting room, bedroom and bathroom, as well as a bedroom and bathroom for her dresser. The Duke's saloon has a similar layout, plus a kitchen. Scottish landscapes by Roy Penny and Victorian prints of earlier rail journeys hang in both carriages.
In the modern age, the cost of the Royal Train has soared, often proving a point of controversy.
Last year it was used only three times, once by the Queen and twice by Prince Charles, at a total cost of £63,255. In 2018, the Duchess of Sussex accompanied the Queen on the train to Cheshire, an overnight journey costing £29,714.
In 2013, Sir Alan Reid, then the Keeper of the Privy Purse, told MPs the current rolling stock had only five to 10 years of service left. The prospect of replacing it, he said, would be a major decision, adding that "the figures are quite staggering".