The riders of the Tour de France will not be required to climb the Mont Ventoux this year but they will find themselves unable to escape its shadow. Some time in the afternoon of Friday 21 July, while pedalling through the vineyards and lavender fields of the Vaucluse, they will glance over to their right and see the Giant of Provence glowering in the distance.

There was a good reason for the Tour’s route planners to avoid the Ventoux this summer. On 13 July it will be 50 years since Tom Simpson collapsed and died at the roadside only 1,300m and a few hairpin bends from the finish line at the summit of the mountain. Ever since that day, images of the banks of scree lining the winding ribbon of asphalt have carried a certain sense of menace, even as they shine bone-white under the midsummer sun.

There is a memorial to Simpson at the place where he fell, usually covered with mementos left by visitors who understand its significance. Even the pros aren’t immune, particularly the Brits. In 2009, when a stage of the Tour finished at the top of the mountain, David Millar tossed a cap towards the plinth as he rode by, while Charly Wegelius lobbed a bidon and Mark Cavendish doffed his helmet. Bradley Wiggins, on his way to third place overall that year, rode the climb with a photograph of Simpson taped to his top tube.

In the foreword to Bird on the Wire, a fine new illustrated biography of Simpson by the cycling journalist Andy McGrath, Wiggins writes: “I felt particularly close to him, and I think I always will. He gave his life for cycling.” Wegelius’s reaction is also quoted. “I surprised myself a bit that I felt the need to make some kind of gesture,” he said.

Simpson during his ill-fated final ride on 13 July 1967. Photograph: Krieger Roger/L'EQUIPE/Offside

Even a non-competitor could share that slightly mysterious response. Driving up towards the finish that day in 2009, before the race, it was impossible to resist the urge to stop the car for a moment and hand a bottle of mineral water to a spectator with a request to place it among the other votive offerings.

Who knows why we do such things? What primitive urges are in play? As the Ventoux recedes over their right shoulders on this year’s stage 19, the riders will pass through the pretty village of Lourmarin, where the modest gravestone of the novelist Albert Camus is usually strewn with objects – pens, pebbles – left by admirers wishing to make some kind of connection with another hero who met a premature death.

But to salute Simpson is inevitably to acknowledge a darker aspect of cycling that refuses to go away, which is why the Tour organisers prudently declined to draw undue attention to the anniversary.

Another five minutes’ riding and Simpson would have reached the summit of the climb stage 13 of the 1967 Tour, in which he was desperately hoping for a good result to restore a faltering reputation. But, as my colleague William Fotheringham wrote in Put Me Back on My Bike, his classic study of the rider, “Simpson’s dying actually began during the first Alpine stage three days before his collapse” on the Ventoux.

A gastric infection had given him a severe and prolonged attack of diarrhoea, which undoubtedly contributed to the dehydration he suffered in an ambient temperature somewhere above 40 degrees while struggling up the last kilometres, helplessly losing time to his principal adversaries, his core temperature soaring as his body ran out of the capacity to sweat away the heat.

But it is the drugs – the amphetamines swallowed earlier in the stage, along with a swig or two of brandy – that people outside or on the fringes of cycling remember, tainting what is in every other way the foundational legend of British road racing.

Tour de France riders observe a minute’s silence the day after Simpson’s death. Photograph: AFP/Getty Images

Simpson was not the first Englishman to move to the continent to try to conquer racing at the highest level – but he was the first to make his effort stick and to establish himself, through his victories in Milan-San Remo, the Tour of Flanders, the Giro di Lombardia and the world championship, alongside the very top riders of the era.

Fotheringham and McGrath both record his regular use of what later became known as performance-enhancing substances but the near-ubiquity of such practices in a very different era and the appeal of his personality make it hard to let admiration be tarnished by disapproval.

In sporting terms, Simpson blazed the trail that others would follow as the momentum behind British riders slowly built to a climax of wins in grand tours and classics. Off the bike he was always ready to play up to a foreign press photographer’s idea of the English gentleman by putting on a bowler hat and sticking a pipe in his mouth.

But among the many wonderful photographs in Bird on the Wire is one of him at home in Ghent the year before his death, 28 years old and looking – with his hair neatly cut in the French college boy style, his fine-knit wool shirt done up to the neck, his face without an ounce of flesh and his eyes black-rimmed – like one of the first generation of mods, styled on a poster from a nouvelle vague movie, maybe with a handful of blues and bombers in his pocket left over from the night before. No wonder the style-conscious Wiggins came to admire him.

As for the mountain, it has a new book all to itself: Jeremy Whittle’s Ventoux, a highly personal account by the Times’s cycling correspondent of the myths and legends attached to the 1,912m peak that stands alone, unattached to any adjacent range. Calling it “the mountain most associated with cycling’s perpetual struggle to exorcise its demons”, Whittle traces the story from the Tour’s first ascent in 1951 through the duel of the damned between Lance Armstrong and Marco Pantani in 2000 and Nicole Cooke’s “virtuoso display of attacking riding” during the women’s Tour of 2006, right up to the questions raised by Chris Froome’s astonishing attack near the summit in 2013. Whittle also takes the risk of channeling Simpson’s thoughts right up to the moment of his death – and brings it off.

Like many people, particularly those who have experienced it first-hand, Whittle takes the Ventoux personally. No other mountain evokes such a superstitious response. Its dark charisma lies behind claims that Tom Simpson “gave his life for cycling”, a romantic notion rooted in our own needs. Simpson gave his life for his career. But the echoes of his tragedy refuse to fade.