A sense of occasion fills the air as Derby Day at Epsom on Saturday promises a festival of punting and bunting.
The Queen is marking the official start of her Diamond Jubilee celebrations at a place where she feels at home.
This day in early June is one she has graced many times in her 60-year reign and, although without a runner in the big race, the great horse lover will savour the atmosphere.
Dressed in royal blue, she was driven down the course as a flag-waving crowd approaching 150,000 packed the Epsom Downs.
Shortly before her arrival, a Red Devils parachute team landed by the winning post with a giant Union flag, while opera singer Katherine Jenkins belted out the National Anthem.
When Her Majesty looks down from the Royal Box at the big race, on which a total of £20m is expected to be wagered nationwide, the chance is she will witness something special.
While the nine-runner field is the lowest since 1907, it boasts potential stories that could make it memorable.
In its 233rd year, favourite Camelot bids to provide the first Derby win for a father/son, trainer/jockey combination with 19-year-old Joseph O'Brien riding for his trainer father Aidan.
The word 'unbeatable' is being bandied about as the 2,000 Guineas winner looks to become the first odds-on shot to win since Shergar in 1981.
"Camelot can only beat himself. He has kept the field size down because people think they can't beat him," said former jockey Willie Carson, who won the Derby four times.
"His pedigree suggests he will stay the distance and all I saw in the Guineas was a horse that stayed - if it was 200 yards further, he would have won by six lengths."
Irish trainer O'Brien has won the race twice before, and although he has saddled 39 runners without success since High Chaparral's victory 10 years ago, the Oaks victory of Was on Friday meant he has won all three English Classic races so far this season.
Son Joseph has only recently turned 19 and has ridden in the race just once before when fourth on Memphis Tennessee last year.
But Carson believes his youth could help during the demanding one-and-half mile trip around the rollercoaster track.
"When you are 19 years old, you don't see the pitfalls, you are not worrying about bad things, whereas at 35 you start seeing what can go wrong," he said.
"The Derby is often won by teenagers or very experienced riders. It's usually a very rough race and jockeys leave their brains behind in the weighing room, but with a small field you don't have to worry about being knocked around."
Second favourite is the Dante Stakes winner Bonfire, who grew up as a foal in the same four-horse Berkshire paddock as Camelot, and victory is likely to spark tearful celebrations.
The horse is trained by Andrew Balding, the brother of BBC TV racing presenter Clare Balding, and she has admitted it would be hard to contain her emotions if he triumphed.
"I think it's odds-on I would cry. It's such a big deal - that's why it's hard not to let your eyes show it," she said.
Their father Ian, who also trained horses for the Queen, won the Derby in 1971 with Mill Reef.
Meanwhile, jockey Hayley Turner seeks to become the first woman rider to win the famous race.
The 29-year-old is only the second female to compete in the Derby, with Alex Greaves finishing last on Portuguese Lil in 1996.
Turner has won two Group One races at the highest level in her career, and was voted Sportswoman of the Year at the Glamour magazine awards during the week, but faces a stiff task on outsider Cavaleiro.
"She rides well and a woman will win one day but it ain't going to happen this year," said Carson.
He won the Oaks on the Queen's horse Dunfermline 35 years ago in Silver Jubilee year and has witnessed the owner's equine enthusiasm.
"She is very much into knowing the personalities of the horses - their mothers and grandmothers," he said.
"She's been breeding horses for 60 years and quite often from the same family, so certain traits keep coming through.
"If you look at her horses, you will see how well named they are. She names all her horses herself."
The Queen will present the Diamond Jubilee Coronation Cup to the winner of that Group One race and will be in good heart after her horse Carlton House, third in last year's Derby, made a winning return at Sandown on Thursday to book a place at Royal Ascot.
She will look out on a sea of red, white and blue as Epsom welcomes a mix of Derby Day racegoers ranging from top-hatted toffs to punters on open-top buses and thousands of Romany Gypsies who traditionally hold a gathering on the Downs.
"We're honoured the Queen starts her celebrations here. When she goes racing, and at Epsom in particular, she seems at her most relaxed," said course managing director Rupert Trevelyan.
"The Derby is always like a big carnival and it's going to be the biggest single street party there is."