Stage 17 of the 2017 Vuelta a España is the first of the final week’s climbing tests for the general classification hopefuls, coming the day after the key individual time trial.
The 180.5-kilometre route from Villadiego to Los Machucos includes three categorised climbs: the Portillo de Lunada, Puerto de Alisas and the finishing climb of Alto de los Machucos.
>> Struggling to get to the shops? Try 6 issues of Cycling Weekly magazine for just £6 delivered to your door <<
The latter is actually the shorter of the three climbs at 7.2km, but what it lacks in length it more than makes up for in difficulty.
Sections of the roughly-surfaced climb feature gradients of over 30 per cent, making it hard to riders to gain traction and keep their momentum – with the very real possibility of some riders being forced to walk some of the steep sections should they falter.
You can watch highlights of the stage here, and read our full stage 17 race report here.
If that wasn’t bad enough, the riders will be mindful of the following day’s stage 18, that again features a summit finish at Santo Toribio de Liébana.
The 2017 Vuelta a España finishes in Madrid on Sunday, September 10.