Merckx went on to win the Tour de France and become an all-time cycling great, but his career would not have been complete without that mythical victory in the spring of 1969

They had a name for it: Merckxissimo. They called him, not affectionately, the Cannibal. When the 24-year-old Belgian reached the Velodrome de Vincennes in Paris after 4,118km of hard-fought racing they gave him the Yellow Jersey, the Green points jersey, the White combination jersey and the title of King of the Mountains. The red and white jerseys of his Faema team dominated the team classification with their leader winning seven stages on all types of terrain, from the flatlands of the North to the mountains of the South.

He was over 17 minutes ahead of the two Frenchmen who shared the podium. He was Eddy Merckx the Magnificent who won every long time trial in the race; Merckx the Munificent who allowed Roger Pingeon to win the stage to Chamonix; Merckx the Merciless who rode for 140km alone through the Pyrenees, over the Soulor and the Aubisque, even though he had the overall victory firmly in his pocket.

"The idea that the Tour is never won until it reaches Paris is finished; Merckx has shattered that legend," eulogised Jacques Goddet. In his Tour de France debut, the Belgian did not disappoint.

He had arrived at the start line in Roubaix under a cloud, having been disqualified from the Giro d'Italia after a failed drugs test. He had to leave the race at Savona, while he was in the lead. The man who turned up at the Tour was no longer the young rider who had burst on to the scene in 1966. He was now "an inaccessible and surly man… and it's an angry champion, in a quest to be rehabilitated, who has crushed the Tour under the heavy weight of his bitterness," or so they editiorialised in l'Equipe.

It was 1969, the year man walked on the moon, Jimi Hendrix wrenched the Star Spangled Banner from his guitar at Woodstock to protest the Vietnam War and John and Yoko went to bed for peace. Concorde took to the skies in Toulouse and on the roads of Belgium Eddy Merckx was lining up for the start of the 53rd Ronde van Vlaanderen.

After three years as a professional, Merckx's palmarès were already the envy of many a modern day rider. Shortly after turning professional with the Peugeot team in 1966 he had won Milan–San Remo and then took the Primavera again the following year, alongside the semi-Classics Fleche Wallonne and Gent-Wevelgem. In 1968 he won the first of his five Giros d'Italia taking all the major classifications to add to his win at Paris-Roubaix. When he added the Volta a Catalunya and the Tour of Romandie to complete another outstanding season, there were few gaps to be filled on his CV. It was already a question not of when he would win a race but how many he would win.

But one of those gaps was his "home" Classic: the Tour of Flanders, or Vlaanderens mooiste (Flanders finest) to those fiercely nationalist inhabitants of Dutch-speaking Belgium. To win the Ronde van Vlaanderen is to become a Flandrien, a hard man. And the hardest of the hard are the Flahutes. The tougher the race, the better they like it.

It's an elaborate French joke deriving from the friendly rivalry between the two countries. It derives from the Dutch word flaauwte, meaning failure or weakness and was once a colloquial term for the angelica plant – a delicate head on a sturdy stem. It came to mean a strapping young lad, naive, a bit soft in the head. On second thoughts, given the Flahute's love of riding hard in the most miserable of weather, it's bang on the money.

Agriculturally fertile and densely populated, Flanders has always been stubbornly of itself, refusing to become part of an independent Belgium until subdued by French troops in 1830. Its flat fields were scarred by some of the bloodiest battles of the first world war, entire villages and cities disappearing overnight in the savage onslaught. The Last Post still sounds daily at the Menin Gate in Ypres.

The epicentre of Flemish cycling is the Ardennes, a tiny hilly region in the south of East Flanders, butted up against the French speaking area of Wallonia where the oldest of the Monuments, La Doyenne Liege-Bastogne-Liege, rounds out the Spring Classics. There's barely room to swing a kitten let alone stage a full blown 200km plus bike race, but that's exactly what Karel Van Wijnendaele decided to do.

A failed cyclist but a better writer, Van Wijnendaele "learned to search with the pen what I could not find with my legs". The editor in chief of the sports paper Sportwereld, he took care of the public relations for a new race, crafted in the image of Paris-Roubaix, that would take the riders on a circuit of the region from Rooigemlaan to the wooden velodrome in Mariakerke – a route carefully chosen to tie in with Gent's World's Fair. Uttering the immortal words "Heren vertrekt!" (Gentlemen, off you go!) the 37 riders of the first Tour of Flanders set off to cover the 324km on the poorly surfaced cobbled roads that came to characterise the race.

But the Ronde of the Koppenberg and the Muur was a long way down the road. The sheer hard grind of those endless kilometres on punishing cobbles was what made the race so gruelling. In the 1920s and 1930s the inclusion of the coast road from Blankenberge to Oostend introduced an elemental force to the race, the riders driven into echelons against the stiff coastal breezes. But the second world war bought the Germans and their Atlantic Wall and the Ronde was forced to find other challenges. Slowly the modern race – with its series of short, tough, ball breaking bergs and muurs – began to take shape.

Oude Kwaremont, Paterberg, Koppenberg, Muur – their names are legend, the cobbled climbs that toughen an already strenuous race into something truly remarkable. The Kwaremont came first in the early days of the race and is arguably the easiest of the bergs; it's longer and drags up more slowly than the short sharp shock of the Paterberg that follows. But as road surfaces improved in the 1960s and the old rough cobbles were replaced with streams of rich black asphalt, the Ronde needed to look elsewhere for its cruelties. And so the race moved into the Ardennes and discovered the Hellingen that have become the true backbone of the race.

The Koppenberg hits the riders with a maximum gradient of 22%, forcing all but the strongest to climb off their bike and run up the cobbles as if the Ronde is nothing but the hardest cyclocross race in the world. Even Merckx was forced to walk up it in 1976. But it is the Muur that everyone is waiting for, the Alpe d'Huez of the Classics. Introduced in 1950, its name literally meaning "wall", the Muur van Geraardsbergen may not be as tough as the Koppenberg according to 1988 winner Eddy Planckaert, but it is the place where the great winners have launched their decisive attacks with riders such as Peter Van Petegem and Fabian Cancellara using it as the springboard for victory.

So steep that it can't be built on, for most of the year it's a pedestrianised zone leading up to the Ouderberg chapel, but for one day in spring – the 14th Sunday in the year – it's the place where every cycling fan would give their soul to be, at the centre of a wall of noise that crescendos as the riders grovel up its cobbled ramps before they swoop to the finish and raise their arms aloft in victory. At least it was until the race organisers switched the finish line from Meerbeke to Oudenaarde. No longer can locals say "the Wall shall choose the winner". With its passing, a little of the soul of the Ronde has gone too.

But in 1969 the Muur was still very much a part of the Ronde van Vlaanderen and it did indeed "choose the winner" though he had already chosen that destiny for himself. Coming into the race on the back of his third success at Milan-San Remo, the future Cannibal stands on the start line in Gent this Sunday in March, the endless sleety rain whipped into the riders' faces by a turbulent, icy north wind.

The pace is high as riders head off into the gloom for the 259km that separate Gent from the finish line in Meerbecke. Surrounded by his bodyguards Spruyt, Stevens and Van de Kerckhove, Merckx is up against the might of the Italians Gimondi, Bitossi, Basso, Adorni and Zilioli, and the French who hope to spoil the Flahute party, Poulidor, Cadiou and Crepel.

A crash brings down "the Finisher", Walter Godefroot and one potential adversary is gone. Merckx sees his chance, seizes it, and the race is on. A punishing acceleration separates the winners from the also-rans and it is this group of 20 or so favourites, of hard men, that Merckx is intent on punishing even though the race is far, far from over.

When Merckx attacks over the Oude Kwaremont, and again on the Muur, he still can't quite break the elastic, invisible band that strings the fractured peloton together. Finally, with 70km left to race, as he passes a municipal stadium where kids are playing football oblivious to the drama being played out on their local roads, Merckx simply changes the rhythm and begins to ride away from his adversaries – first hardly a bike length, creating an imperceptible distance between himself and the chasing pack, then inexorably moving further and further away and into the rain.

Guillaume Dreissens, his directeur sportif, warm and dry behind the wheel of his Peugeot 404, wonders just what the hell his rider is thinking. He pulls alongside the sodden Merckx, tells him that he's crazy, and he should sit up and wait for the chasing pack. "You'll never survive in the headwind!" he screams. Maybe his words are snatched by the wind but the Belgian takes no notice and just ploughs on into the murk and the rain leaving a single expletive behind him as he heads on into the storm.

Anger drives him as it so often will in his career. A desire to make the two fingers more than just a metaphor. Merckx is determined to show these fuckers – his rivals and directeur sportif – who's boss. For 25km he battles the wind alone, stiffening over the drops like a chilled cadaver, refusing to sit up or give up, teasing his meagre lead to a solitary minute.

The wind drives the rain into his face and the cold eats through his kit and into his bones. And then the road forks at Niederbrakel and the invisible thread snaps at last and Merckx is free. He stamps more forcefully on the pedals, pushing harder and harder against the clock, forging seconds into minutes in the face of his inexorable acceleration. When he crosses the finish line he is five minutes and 36 seconds ahead of a shattered Felice Gimondi.

It was the day the myth was born – when a grocer's son from Brussels became a Lion of Flanders. Later that year he added victories in Paris-Nice and Liege-Bastogne-Liege, before he was finally crowned King Eddy on the roads of France. There was more to come: more Grand Tours, more Classics, more stage races. Records tumbled in his wake and have never been bettered: most career victories (525), most wins in a season (54), most Classics victories (28), the greatest number of Grand Tour wins (11) and so on and so on. He was the Cannibal, the Ogre, the Martian, a rider hors norme.

"Panache!" cried l'Equipe, "Chapeau Eddy!" But there was pragmatism in his coup de folie. The major difficulties of the race were too far from the finish line to force a decisive selection. And where was the sense in towing a fast finisher like Basso to the line to be ignominiously outsprinted? He would joke later: "I've won almost every Classic. Van Wijnendaele and co started to wonder if I'd ever win theirs!" But after abandoning in 1966 and managing no better than third and ninth in his next two attempts, all Flanders was beginning to despair that their great champion would never win the race. That morning's Het Nieuwsblad had scathingly announced that Merckx simply didn't have what it took to win the Ronde. Maybe that was the spur that kicked him into action on that stretch of false flat outside the hamlet of Vollezele. Merckx had read it. His reaction: "We'll see."

Lomme Dreissens would claim that Merckx's apparent suicide mission had been a carefully planned tactical masterstroke all along. Relations between the two men weren't great, and Merckx was furious. Later he would recount the incident, shrug his shoulders and say "typical Lomme, eh?"

He would win again, in 1975, in what was fast becoming the twilight of his exceptional career. This time he attacked decisively on the Oude Kwaremont, 100km from the finish line. Only Frans Verbeeck could stay on his wheel and then only barely. With the finish line 5km away, Verbeeck could resist the metronomic pace no longer and fell away, leaving Merckx to cross the line alone.

"I'm sure he could have dropped me earlier, and if he had he would have won by 10 minutes" recalled Verbeeck, himself no slouch on the roads of the Ardennes, "but I think Merckx liked the way I raced, so he made sure that I took second." Merckx said it was probably his greatest physical achievement in any race, that he had never ridden harder. But the rain stayed away and the Classics are always more properly themselves when raced in a diluvian downpour.

Later that year the unthinkable would happen. Merckx would lose at the Tour de France and Merckxissimo – that extraordinary eight-year period when one rider transformed himself into the greatest cyclist ever – was over.

Dominance is a word that can be used but not merited. But Merckx was suffused with the passion to win. Was it fair to win so often, so much? "The day when I start a race without intending to win it, I won't be able to look at myself in the mirror. I'm not saying that every time I race I go to the very limit of my strength. But when the opportunity appears I consider it immoral not to take them," he replied.

Goddet said of him in 1970: "Absolutely triumphant, Eddy Merckx entered Paris in imperial dominance, admired but wrapped in a curious and somehow indefinable halo of genius."

Can a man who rides a bike for a living ever be considered a genius? Look to the Latin: genius is defined as "attendant spirit present from one's birth". Merckx wanted to be a cyclist "from the age of four, when I listened to the Tour de France on the radio." He was junior World Champion at 19, senior World Champion at 22. But Merckx's particular genius was about more than simply winning races. It lay in his ability to show us only what he wanted us to see on the road, the multiple Merckxs of our imagination.

A smart and complicated man, he allowed us to project on to that impassive face our own desires for invulnerability. Like an Easter Island statue, he was colossal and mysterious yet all too human. What motivated Merckx was, in the end, what motivates us all: desire, pride and spite.

The "little rat" Cyrille Guimard said of him: "It is our failures that make us grow, make us popular, make us human. Not Eddy Merckx." And Merckx was a winner, distancing himself from us, the failures. Almost forcing us, daring us to choose Ocana and his fragility. Poulidor, the eternal second, was kinder and perhaps summed him up best: "He was a perpetual worrier, always believed he wasn't at his best, that he had some problem or other. But he was a winner, unlike myself who just enjoyed the sport, win or lose. He never tolerated failure – he felt he was letting his fans down."

And then there's the twist in the tale – isn't there always, in all the best stories? Rewind to 9 September 1969 at the Pierre Tessier velodrome in Blois. Merckx is competing in a derny race with his pacer Fernand Wambst when they get caught in a crash. Wambst is killed outright, Merckx suffers head and spinal injuries and twists his pelvis. From then on he rides in constant pain. He endlessly adjusts his saddle. He says "cycling is pain for me" and claims he is never again the same rider. "I was never as strong again in the mountains. Without the crash I could have won more Tours."

How his rivals must have wept.

But as he stands on the podium in Meerbecke all that is ahead of him – the adulation and the disappointments, the anger and the pain. Someone asks him "why did you do it Eddy?" He thinks about it. His answer is simple: "If I'm going to have to do all the work, I might as well do it alone." Merckxissimo.

• This article appeared first on 100 Tours 100 Tales

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