This is what it was all for. All those months of early mornings, rising with the mist still on the fields, watching from the Jeep as the horses’ breath catches first light; all of it for this moment. As the starter lowers the flag, thousands of hearts are in thousands of mouths. Over the next two to three miles, hooves pound the earth, carrying forth the hopes of the jockeys, the trainers, the owners and the fans.

In the vernacular, the sound is described as a ‘thundering’ of hooves, but thunder doesn’t shake the earth quite like the passing of racehorses. Thunder doesn’t see tens of thousands congregating at racecourses in their finest clothes. No one lays bets on thunder. No, this sound is a thunder from within, a heart beating faster than it has ever beaten before, a pulse soaring from the sight of watching your horse running against its rivals. But fans who flock to the Cheltenham Festival see only half the story, if that. Speaking to Jamie Snowden, founder and trainer at Jamie Snowden Racing, reveals the effort involved in getting a horse ready to race.

“Dawn to dusk, and beyond,” is how he describes it, “and three hundred and sixty five days a year. It becomes your way of life.” Having ridden horses from a young age, Jamie took a gap year after school, which he spent racing around the world, then attended the Royal Military Academy at Sandhurst. Training horses though, was always on his mind. “The buzz I get out of training a winner is bigger than the buzz I get out of riding a winner,” he says. That buzz saw him start out on his own in 2008, following stints with Nicky Henderson and Paul Nicholls, both big names in the business of horse training. He had one horse and one employee. Today, he trains forty horses and employs fourteen members of staff.

“We’re in the entertainment business,” he says. “So we have to make sure the owners have a good time.” Racehorse owners are involved at every stage of the process, watching the horse progress, deciding on tactics, chatting to the jockey, and watching from the stands on race day. Jamie winds down after the races with a drink with the owners. “If it wins, there’ll be champagne,” he says with a smile. With prize money of almost £4.6 million at stake over the four days of the festival, it’s not hard to see why. But he never loses sight of the horses’ wellbeing. “Every horse is an individual,” he says. “I have my training regime, but it needs to be tailored to the horses. We need to decide when a horse needs routine, and when it needs variety.”

As well-dressed crowds pour into the Cheltenham Racecourse, clutching the Racing Post or the festival’s racecard, the atmosphere is buzzing, as they soak up the live music or stop for the first pint of the day. Many head straight for the cacophony of the betting ring, where bookmakers smile as punters lay hard-earned notes on the outcomes of the races, in a language of odds, each ways and favourites. Both the punter and the bookmaker still hope to be smiling later in the day, but if one ends the day upbeat, the other generally doesn’t. In all, over £150m is bet on the Cheltenham Festival every year: in person, in betting shops around the country, and online. For some, there’s the academic poring over the racing pages of the newspaper, examining the form and weight of the horse, the ground it’ll be running on or its past performance over this distance. For others, it’s as simple as liking the horse’s name. Either strategy can lead to success.

The thunder starts with the Cheltenham Roar, a massive coordinated outpouring of sound from thousands of pairs of lungs that greets the start of the first race of the festival. Then the pounding, the drumming, the beating hearts all form one, as the fans, pressed together in the stands, crane their necks to catch sight of the action, as the horses gallop round the course, jostling for position. A strong start doesn’t mean a strong finish, and a mistake at a fence can cost horse and jockey dearly. By the end of the day, white betting receipts litter the ground, evidence of the unpredictability, the rollercoaster of emotions, the buzz of being swept up in a whooping, cheering crowd, and the winning (or losing) of sweet, sweet money.

Win or lose though, both the fans and the trainers will be back. Some punters have been coming to Cheltenham for decades. Some stables are onto their third generation of trainers. It’s become their way of life. They’re seeking that impending rumble that tells them of the oncoming excitement, the potential glory, the bragging rights and the prize money. They’re storm hunters, all of them, chasing the next bout of thunder in their hearts.