A cheer will go up in Liverpool at 1:45 pm Thursday. That’s when the runners set off in the opening race of the three-day Aintree festival, culminating in the Grand National at 5:15 on Saturday.

The National will see 40 runners facing 30 fences over 4 miles, 2 furlongs, and 74 yards (just short of 7,000 meters) for the ￡500,000 ($708,000) first prize.

The race is one of the biggest spectacles on the British sporting calendar. Even more than the Derby, it is the one race guaranteed to attract an audience of millions around the world. The once-a-year punter eagerly studies the form – or looks for a horse with a name similar to that of their cat – in search of the winner.

But there is more to the Grand National than simply trying to pick the winner. It is a race steeped in history, controversy, and – most important – romance.

The history

For years, the conventional wisdom was that the winner of the first Grand National – run in 1839 – was the aptly-named Lottery. However, the sport’s historians now say that the race was first run in 1836 and was won by The Duke, ridden by Martin Becher, after whom the iconic Becher’s Brook is named.

The race was transferred to Gatwick during World War I. In 1928 came a race that is simply unthinkable today: 41 of the 42 runners fell, leaving 100-1 outsider Tipperary Tim to come home alone.

The drama of that race wasn’t matched until 1956, when the Queen Mother’s Devon Loch mysteriously collapsed with the race apparently won. In 1967, another 100-1 outsider, Foinavon, won the race, thanks to what Irish commentator Michael O’Hehir famously described as “a right pile-up” at the fence after Becher’s Brook, now known simply as “the Foinavon.”

By the 1970s, the Grand National appeared to be on its last legs. There was uncertainty over the ownership of the course and every race was billed as the last one. The race was probably saved by a horse – the legendary Red Rum, who won the race three times and finished second twice from 1973 through 1977.

1981 brought the story of Bob Champion and Aldanati, later made into the film “Champions.” Since then, the National has brought us false starts, bomb threats from the IRA, and another 100-1 winner in 2009, when Mon Mome won by 12 lengths to leave punters scratching their heads…

The course

Over the years, the fences on the National course have been modified, notably to remove “the drop” from the landing side of some of the fences, so falls are less likely now. The race organizers also take pains to water the course, meaning that the race is unlikely to ever be run again on firm going. That also means that Mr Frisk’s course record of 8 minutes and 47 seconds, set in 1990, is unlikely ever to be beaten.

Despite that, the National remains a fearsome test, requiring jumping ability and stamina, especially if – as looks possible this year – there has been a lot of rain and the going is soft. It is the only race in the world where the fences are almost as famous as some of the winners. We’ve mentioned Becher’s Brook above; there is also the Chair (the highest fence on the course and jumped just once) and the Canal Turn, where the horses have to turn 90 degrees to the left immediately after jumping the fence.

The statistics

If you are looking for the winner this year, where should you look? Maybe the stats can provide a guide…

The age group most likely to produce a winner is between 8 and 10. The Grand National is a tough test for a horse younger than 8 and, by the age of 11, horses are starting to lose the speed that is essential in a modern Grand National.

It used to be the conventional wisdom that a horse couldn’t win the race carrying more than 11 stone. That doesn’t seem to be the case nowadays, as the increased prize money continues to attract classier horses to the National. Neither does previous experience of the Grand National appear to be the essential it was once considered to be.

Despite the romance of Tipperary Tim, Foinavon, and Mon Mome, recent winners have been priced at shorter odds. Three of the past five winners have been returned at 25/1.

A first for Katie?

Last year’s winner, One for Arthur, was the first winner from Scotland since 1979. But there could be an even bigger piece of history made this year, as Irish jockey Katie Walsh bids to become the first woman to ride the winner. Katie finished third on Seabass in 2012, but now rides Baie des Iles, currently priced at 28/1. And what was that about romance? The horse is trained by her husband.

So at 5:15 BST on Saturday, the world will hold its collective breath as the runners approach the starting tape. There will be 40 runners but only one winner. The main thing, obviously, is the hope that all the runners and riders come home safe and sound.