It’s an iconic London structure, a globally recognised palace, and the Queen’s home.
Now Buckingham Palace has been mapped out afresh by an architect to give an insight into the scale of this enormous London house.
The palace has 775 rooms, which can be divided into three sections - the central block, the Queen’s apartments, and the east front.
The central block contains many of the state rooms, some of which will be easily recognised by royal watchers.
Here you will find the grand staircase, with red carpet and pictures of the Royal Family lining the walls.
The central block is also home to the Music Room, where Prince William was christened, and the Green Drawing Room, where the Queen’s weekly audience with the prime minister is held, in usual circumstances.
The Music Room was used for four royal christenings - Charles, Anne, Andrew and William - but hasn’t been used more recently.
The floor plans give an impression of how grand a scale this is all on - the ground floor of the palace is 420ft long and more than 180ft across, while the top floor of this wing is 370ft by 120ft.
The central block also holds the state drawing room, which is where Prince William and Kate had their wedding reception in 2011.
The 1844 room is also in this wing, and will be well recognised by many. It’s where the Queen receives many distinguished guests, including presidents and celebrities.
It’s been dubbed the most important room in the house because of the guests it receives. It was named after the year Russian Tsar Nicholas I visited.
The Regency Room is familiar too, often used by the Queen for her annual Christmas message, which is broadcast on television and radio every year.
While the Queen has access to 775 rooms when she is in her London home, she only uses about six regularly, in her private apartments.
Here the Queen has her bedroom, a private sitting room, dressing room and bathroom. They are off-limits to everyone except Her Majesty and those close to her.
Those touring the state rooms during the summer opening of the palace won’t be lucky enough to catch a glimpse of her unmade bed or breakfast leftovers.
There is also a room here which the Queen can use to receive the prime minister each week, and where she meets the Chancellor of the Exchequer before the budget.
In this section, the researchers found a set of rooms with unclear use - the Bobo MacDonald’s suites. Margaret MacDonald, known as Bobo, was the nanny, dresser and confidante of the Queen until her death in 1993 at the age of 89.
What these rooms are used for now is not clear.
In this wing you can also see a set of rooms for Prince Philip, though the 98-year-old is rarely in Buckingham Palace these days.
He spends most of his time in their home in Sandringham, and joined the Queen for Easter Court at Windsor Castle this year. However, due to the coronavirus outbreak, it’s unlikely he will be going back to Norfolk in the foreseeable future.
The final section the team examined is the East Front. This section is undergoing renovation work this year some of which was shown on Buckingham Palace’s Instagram account as early 19th century Chinese wallpaper was painstakingly removed by hand for repair.
In this wing sits the Centre Room, previously called the Chinese Dining Room. This room was largely furnished with items from the Royal Pavilion in Brighton, which was once a royal residence.
The pavilion was sold in 1840 to provide the funds for the Marble Arch, which used to sit closer to the palace, to be moved. This was so Queen Victoria and Prince Albert could extend and get the necessary nursery rooms and living space in the home.
The East Front is the part of the palace which is best known today to tourists and Londoners, but it was not actually finished until 1850, and so would have been the newer wing for many Victorians.
It was remodelled in 1913 to its present form.
It’s also where the balcony is, where the Royal Family stands to watch the RAF flypast, and where Prince William kissed his new wife on 29 April 2011.
The room behind the balcony is a private part of the palace.
Buckingham Palace was originally called Buckingham House, and is still affectionately known as Buck House by some, and was owned by the Duke of Buckingham after whom it was named.
It once nearly became the House of Commons - after the fire at the Palace of Westminster in 1834, it was briefly considered to move parliament there.
Queen Victoria was the first monarch to live there full time, but she abandoned it for a time after the death of Prince Albert.
Nowadays, it’s lived in by the Queen during the week for most of the year, who then spends the weekends in Windsor.
It’s opened up for a number of weeks during the summer, and about 50,000 people visit, either to see the state rooms, or to be hosted in the palace gardens at a party.
The floor plan project was devised and commissioned by HomeAdvisor and carried out by architect Jelena Popovic.
Jonny Addy, the project leader, told Yahoo UK about the reaction when the team realised the scale of the palace.
He said: “In all honesty, we actually didn't realise the scale of the palace (or the project) until we began researching.
“We initially planned for the research to take two weeks and it ended up taking two months. It wasn't until we started going through the thousands of photos that exist of the palace that we realised just how massive it is.
“It was a bit of a shock! But it's such a beautiful building and so iconic that our shock soon turned to delight.”
He added that it was one of the biggest projects his team has ever done, but that they “love to take on a challenge.”
He said: “As soon as we found out that no publicly-available floor-plan existed, we knew we had to make one.”
The team researched the palace from available information through the Royal Family’s website, the Royal Collection Trust and Historic England.
But there are still some sections of the palace which remain a mystery, used by palace staff.