By Martyn Herman
SERRE-CHEVALIER, France (Reuters) - The Col de l'Izoard, where the decisive battle in this year's Tour de France will be waged on Thursday could, in the words of race founder Henri Desgrange, "make a mule whimper".
The devilishly steep 16km ribbon of tarmac snaking up to 2,360 meters in the French Alps awaits the peloton on stage 18 and represents the last major obstacle for leader Chris Froome.
If the yellow-jersey wearer is the man leading them across the lunar-like Casse Deserte, with the summit finish in sight, those burning up their legs behind him will know the last chance for him to crack has probably vanished.
Barring calamity for the Team Sky rider bidding for a fourth victory and third in a row, the race will be as good as won if he does not get ambushed on one of cycling's most iconic climbs.
The Izoard appears in plenty of Tour de France folklore.
High up on its barren slopes can be found two plaques celebrating the lives of two of the sport's greats -- Fausto Coppui, winner in 1949 and 1952, and Louison Bobet who also conquered Izoard while winning in 1953, 1954 and 1955.
Those who pass them on the upward slog will probably be suffering too much to notice as they tackle the last sections of a hellish 16km climb averaging a 6.9 percent gradient but ramping up to nearly double that at times.
Unrelenting and unforgiving it is not for the faint-hearted.
But it is where epic cycling feats have been achieved and there could not be a more symbolic place for French hope Romain Bardet, who along with Columbia's Rigoberto Uran is 27 seconds behind Britain's Froome, to turn himself into a national hero.
That is exactly what Bernard Thevenet did in 1975 when he left a struggling Eddy Merckx in his slipstream on Izoard and went on to glory in Paris, effectively ending the Belgian's stranglehold of the world's greatest cycle race.
"It's wild and empty," Thevenet once recalled. "There's nothing there -- barely a plant or a tree among the rocks."
Unlike on the 33 other appearances of the Izoard on the route, Thursday's 179km stage from Briancon actually ends on the summit -- ensuring a lung-bursting sprint.
Cannondale Drapac team manager Jonathan Vaughters, once a specialist climber and team mate of Lance Armstrong, said Izoard is a climb that can play tricks with even the best mountain men.
"Of the Alpine climbs its probably the one that has the most irregular gradients," he told Reuters. "At high altitude changing speed and rhythm is more difficult than lower climbs.
"It's very hard to deal with that. The summit finish makes a difference too because with no descent, the guys will not be leaving anything in the tank. It's going to be decisive."
Team Sky chief Dave Brailsford describes Izoard, a climb he knows like the back of his hand because of his father who has been a mountain guide and ice climber based in Briancon for 40 years, as one of the most remarkable stages in cycling.
He also believes it offers the perfect battleground for Froome to kill off his rivals once and for all after keeping them under control on the daunting Galibier on Wednesday.
"On Izoard we can be a bit more offensive and take it on," Brailsford told Reuters
"Izoard is right up there with the best but it's usually climbed en route to somewhere else. The fact that it's a summit finish makes it a big, big day for the race and for the team."
(Reporting by Martyn Herman; Editing by Toby Davis)