Racing up Alpe d'Huez can be either a career-defining moment or a dizzying experience. The D211 is the official name of the road that zigs and zags up the mountain and to the ski resort at the top, 1,120 metres (3,670 feet) gained from the base at Bourg d'Oisans in just 13.8 kilometres (8.6 miles).
The D211 is most famous for its 21 switchbacks, firmly back as a protagonist on stage 19 at this year's Tour de France, but a 3.7km section will also play a decisive role in stage 20 as the final segment of a mountaintop finish circuit following the Col de Sarenne ascent.
