Of all the entries in the lexicon of track and field, the Marathon occupies a unique place.
It may not enjoy the glamour of the 100 metre sprint, or even of the ‘middle distance’ 1500 metres. Yet its very scale inspires the awe of ordinary mortals.

Paradoxically, it also inspires hundreds of thousands of those mortals to submit themselves to its gruelling regime every year, in every corner of every continent on the planet.

However, it is the astonishing feats of will and endurance that the marathon regularly evokes from its top practitioners that lend it a special, epic quality – which is entirely appropriate, given its heroic origins in ancient Greece.

In 490 BC, King Darius of Persia landed at the town of Marathon with an invasion force of 20,000 men, intent upon conquering Greece. The Greeks were outnumbered and sent a request for assistance to the Spartans. The request was carried by a runner called Pheidippides, who covered the 145 miles in two days.

As it turns out, the Greeks overcame the Persians relatively easily – and poor old Pheidippides had to run back to Athens to break the news. He managed to address one word to the king ‘Nenikhamen!’ (rejoice, we conquer) before dropping dead.

The rebirth of marathon running was initiated by a Frenchman, Michel Breal. A friend of the father of the modern Olympics, Pierre de Coubertin, he argued that the introduction of an event so deeply rooted in Greek history would add weight to the revival of the games in Athens in 1896.

The first race was won, satisfyingly, by a Greek. Spiridon Louis, a labourer, was accompanied throughout the race by his bowler-hatted coach on a push bike. He stopped en route to eat slices of orange provided by his girlfriend, and finished in 2:58:50.

He was showered with presents – watches, clothes, guns and for some reason, a sewing machine. He was made an offer of marriage, too, which can’t have impressed the girlfriend much. But he turned them all down and returned to the countryside, asking only for a horse and cart so he could better deliver water to the villagers.

Seventeen runners competed in that first, modern marathon. None could have foreseen how the movement would gain impetus over the next century.

The current, official distance of 26 miles 385 yards was adopted after the 1908 Olympics in London.

In 1966, Roberta Gibb became the first woman to run in a major marathon – the Boston – by hiding behind a bush until the start, then joining the male athletes.

In 1975, Boston became the first marathon to recognise the disabled athletes who are now such an integral feature of the event.

As if it weren’t enough to subject the joints and tendons to the stresses of that implausible distance, the event’s history is peppered with almost superhuman accomplishments. Last year, only months after a close encounter with death and consequent major heart surgery, Sir Ranulph Fiennes, with his companion Mike Stroud, succeeded in running seven marathons in seven continents in seven days.

By the end of the Singapore marathon, Stroud was urinating blood and his blood enzyme levels were so low that his muscles were literally beginning to disintegrate. And yet he managed somehow to carry on, running in London and Cairo before a grand finale in New York.

What is it that enables the spirit to triumph against such adversity? “The quality you really need with all these tests,” Stroud believes, “is a bad memory, so you can remember the good parts and forget the bad.”

Sir Ranulph must have a highly selective memory – he’s running the Singapore marathon again, as part of a team in the Standard Chartered Bank’s four-marathon series, the Greatest Race On Earth.

Another glutton for punishment is Lloyd Scott. Last year he undertook an underwater marathon for his leukaemia charity in 2003, walking the length of Loch Ness, Scotland, in a diving suit and surviving a painful five-metre fall from a ledge en route.

And then there’s Norway’s Grete Waitz who was turned down for an official place in the New York marathon in 1978, but ran it anyway. Fantastically, she won it, even though she’d never run further than 12 miles before.

Throughout the century of its existence, region after region has dominated the marathon.

Scandinavia emerged during the Antwerp games of 1920, with ‘Flying Fin’ Paavo Nurmi becoming a national hero when he broke a seven year-old record by four minutes.

Then it was the turn of the Far East.

In 1936, the Korean Sohn Kee Chung won the Olympic marathon in Berlin (although he was forced to run under a Japanese name). His victory signalled the beginning of Korea’s mastery of the men’s race that was to last for decades.

Japan, on the other hand, has produced a long line of brilliant female marathoners – not least, the winner of the Athens Olympics, Mizuki Noguchi.

Then it was the turn of Africa. Ethiopian Abebe Bikila, one of Haile Salassie’s Imperial bodyguards, won the Rome Olympic marathon in 2:15:16. Bare foot!

For twenty years, Ethiopia seemed invincible. But then the Kenyans appeared, almost from nowhere, and stole the marathon crown. Paul Tergat clocked up an astonishing 2:04:55 in Berlin in 2003 – while the new wave of Kenyans includes the awesome Daniel Njenga and Catherine Ndereba.

As the times tumble inexorably down, we can only wonder where the crown will reside next. South Asia and the Arab world have only just begun to flex their muscles.

Indeed, Standard Chartered’s Greatest Race On Earth was conceived partly to encourage the development of the sport in regions other than Europe and the USA.