Tour de France: Is Wiggins the greatest British sportsman ever? With only today's ceremonial stage into Paris's Champs-Elysées left to race, Wiggins's lead in the 3,497km three-week Grande Boucle is now 3mins 21secs ahead of his Sky team-mate Chris Froome, with Italian Vincenzo Nibali in third. By convention, the Yellow Jersey is not attacked on the final stage. Regularly named the largest annual sporting event on the planet, the Tour is also rated one of the most fearsomely difficult. With 21 stages, its challenges include up to 5,000m of climbing in the Alps or Pyrenees in a single stage - imagine climbing Ben Nevis three times in a single day. Treasured by the French as a showcase event for rural France, with TV images frequently dwelling on chateaux and lush green countryside as much as the riders themselves, Le Tour has also been tarnished by some of the worst drugs scandals in sport. Revelations of organised doping in the top-flight Festina team in 1998 and the ongoing investigations into seven-time winner Lance Armstrong are among low points. If the race has gone through harsh times in the past decade, Wiggins himself has had to overcome some hard personal obstacles, ranging from a tough inner-city upbringing in Kilburn, north London, after his father abandoned the family when he was two years old, to some personal battles with alcohol in 2004. Previously best known as a triple Olympic gold medallist for Great Britain as a track racer, Wiggins's Tour success has bolstered his profile. Posters on the Mumsnet website were so enamoured by him that they composed poetry. One fan, with the handle Hassled, enthused: "Oh Bradley - your thighs/Cause fluttering and sighs. /My eyes are like saucers /You've turned me into Chaucer." Born in Ghent, Belgium, "Wiggo" grew up in Kilburn where his mother, Linda, still lives. His heavy-drinking and violent Australian father, Garry, himself a talented cyclist, was, in Wiggins's own words, a "car crash" as a partner and a parent. In his autobiography, In Pursuit of Glory, Wiggins tells that he did not hear from his father between an outing to London Zoo in January 1983 and a phone call in 1997. The young Wiggins was nevertheless attracted to his father's sport and started racing at London's Herne Hill velodrome when he was 12. By the age of 20, he had won his first Olympic medal and the following year signed for the professional Linda McCartney Racing Team. Wiggins has admitted he struggled after securing a hat-trick of medals in the 2004 Athens Olympics and fell into binge-drinking. He went on a bender for months that ended only with the birth of his son, Ben, in March 2005. He has said: "I hardly drew a sober breath for nine months." The cyclist went on to win two Olympic gold medals in Beijing in 2008, just months after his father, Garry, was found unconscious in the street in Aberdeen, New South Wales, and died in hospital. It is thought his father had been beaten up. The cyclist, who lives with his wife Cath and children, Ben and Isabella, in Eccleston, Lancashire, has raced with Team Sky since 2010. His outspokenness on the issue of doping has won him fans. He was part of the Cofidis team that pulled out of the Tour in 2007 after team member Cristian Moreni failed a doping test. On the way home, Wiggins put his kit in a dustbin and vowed never to race in it again. Earlier this month, he said that if he felt he had to take drugs, he would rather stop racing and "work in Tesco stacking shelves." Wiggins's title comes after an appalling crash forced the Briton to quit the Tour last year with a broken collarbone, and a disappointing 24th place in the 2010 race. This time he has ridden a faultless Tour, snatching the lead in the Vosges mountains on stage seven and then reinforcing his domination of the general classification with a superb time trial victory three days later in Besançon. Ably supported by the Sky team, the mutton-chopped, 6ft 3in tall Wiggins then defended his lead through six daunting mountain stages in the Pyrenees and Alps. Not even a flare, fired by fans, which burned his arm or having to weave his way through tacks scattered by hooligans on a 60mph descent was able to stop him. The net result will be that three years after Wiggins equalled Scot Robert Millar's previous best GB result of fourth, the Tour will finally see a Briton in top spot. The second place for Chris Froome, born in Nairobi to British parents, and six British stage wins - with perhaps another for reigning world champion Mark Cavendish today - underlines the extent of the country's domination. Wiggins's victory in an event that has resisted his nation's athletes for so long also acts as the ideal curtain-raiser for British athletes ahead of the Olympic Games. Both he and Froome will take part in the road race on Saturday, where they will support Cavendish in his attempt to take Britain's first gold of the Games, and again in the time trial - Wiggins's big target - the following Wednesday. But it is the Tour win that would be the "greatest achievement by any British sportsperson ever," according to four-time Olympic champion Sir Chris Hoy. Tour challenge It is the relentless climbing and falling, the soul-destroying length of the Tour de France that breaks men and makes it one of the most physiologically demanding events on earth. Sure, its US rival, the Race Across America, covers greater distances, but it's far flatter and usually over in 10 days. The Marathon des Sables, where runners traipse 151 miles through the Sahara Desert is over in just six. The physical demands are like no other. Nearly half a million pedal strokes cover 3,497km through some of the most rugged terrain in Europe; the race demands the same level of fitness as running a marathon for 20 days consecutively.Even to be in contention, competitors will have to ride double the miles slogged over by the average competitive cyclist. The climbs are what make Le Tour so brutal. Cyclists have to battle through about 25 mountain courses in the Alps and the Pyrenees. With more than 21,000m of climbing, it is like scaling Mount Everest three times. Bradley Wiggins put in 100,000m of climbing to prepare for the race. During the race contenders will burn 8,000 calories per day. The biggest climb on any single day is equivalent to nearly 10 Eiffel Towers. Cyclists plunge down mountains at speeds of up to 80mph. Such dangers are accentuated by often wet and slippery roads. To date Le Tour has claimed four lives. Kunal Dutta