The peloton will endure a 214.5km leg from Pau to Peyragudes on stage 12, via the climbs of the Col de Ares, Col de Menté, and Port de Balès, before a finish at the summit of the Col de Peyresourde.
A day later, on stage 13, the riders will encounter a brutal trio of first category climbs, each carrying them above 1,000m. The Col d’Agnes at 1,570m represents the main course of a menu that most in the peloton will find distinctly unappetising. Expect the GC contenders and climbing specialists, however, to feast while they can.
This 104th Tour de France has not been billed as one for the climbers, but perhaps the comparative lack of mountain stages will encourage the strong men to give everything when this particularly savage brace arrives just past the midway point. Nothing, however, will prepare them for the appearance of the Col d’Izoard in the closing week.
The Izoard looms at the climax of stage 18. Some 2,360 metres separate its peak from the valley floor. An average gradient of 7.5 per cent - enough to deter mortals - barely describes the challenge.
Picture the scene. The road ahead is long and winding, snaking into the distance like a giant serpent; its tarmac coils rising steadily to some unseen summit. All the while the sun beats down remorselessly. It is not only the gradient must be overcome, but the temperature too.
More revealing are the five kilometres pitched at gradients of nine per cent and more, including the sudden ramping up from seven to 10 per cent after seven kilometres, or the 10 per cent ramp that marks the final kilometre.
Consider also the Casse Déserte, where any relief granted by a momentary flattening of the road is cancelled out by the utter desolation of the surroundings: a rocky wasteland that amplifies the heat and glare cast down by a pitiless sun.
The Izoard is a professional cyclist’s Room 101: a peculiar punishment that might have caused even Orwell to recoil. This is no theatre of dreams, despite hosting some of the most compelling dramas in the Tour’s rich history, notably a duel between Italian arch rivals Fausto Coppi and Gino Bartali in 1949.
The modern peloton will find the road no less forgiving, but they can count on lighter and more technically advanced clothing to reduce the climatic ordeal. This will be the only comfort they can count upon, however. The Izoard represents only the brutal conclusion to a two-day rendezvous with suffering in the Haute Alps. Before reaching its slopes, the riders must navigate the climbs of the Croix de Fer, Télégraphe and Galibier on stage 17, and scale the Col de Vars on stage 18.
This is terrain to inspire the sort of heroic ride with which the Tour is synonymous. The climbing specialists and the strong men who hope to win the race overall will welcome the rising roads of the Alps and Pyrenees, while those seeking merely to make it to Paris will hope for nothing more than survival. Resilience, an understated quality, will be paramount.