Perhaps one of the most eagerly-anticipated stages of this year’s race is stage 15, which finishes against the stunning backdrop of Lake Covadonga.

The second of three days in the mountainous Asturias region, the final climb – up to the iconic lakes – is one of two ‘ESP’-categorised ascents on this year’s route.

It is notable for kicking up to 17.5 per cent in the final 200 metres, with a series of false flats on the way up too.

An undulating climb, particularly in the final four kilometres of its 12.2-kilometre length, the average gradient of 7.2 per cent conceals its true difficulty.

The twisting, hairpin-laden HC climb is a popular one on Strava, with 632 riders having attempted it, the fastest time being 41:25 – an average speed of 17.4km/h.