Collado de Prao Poyo o del Miradero

Overview

The Collado de Prao Poyo o del Miradero is a hors catégorie (HC) climb, the hardest rating on the scale, and it earns that label without apology. Over 12.1 km the road climbs from 950 m to a summit of 1960 m, a net elevation gain of 1010 m at an average gradient of 8.33%. That average alone would put it among the toughest sustained efforts you can ride, but the headline number is the 31.92% maximum gradient — a wall steep enough that momentum, not just fitness, decides whether you stay upright.

How the Gradient Unfolds

An 8.33% average across 12.1 km means there is almost nowhere to recover. On a climb this long, the average is a floor as much as a target: for every gentler stretch, the road pays it back with something far harder. The gap between the 8.33% mean and the 31.92% peak tells the whole story — this is not a metronomic drag but a climb of violent ramps stacked on an already-punishing base. Expect the steepest pitches to arrive without warning and to demand a full-body effort, then to release you back onto a gradient that would be the crux of most other climbs.

Pacing Notes

On a 12.1 km HC effort, discipline beats bravado. Anchor your pacing to your FTP and hold the early kilometres just under threshold, because the 8.33% average leaves no flat to hide on and the 31.92% ramps will force you well over your limit whether you like it or not. Bank nothing you cannot repay. If you are unsure of your number, run it through the FTP estimator before you commit, then ride the lower slopes conservatively so you have something left when the wall hits. Getting the pacing wrong on the first third turns the final push from 950 m up to 1960 m into a survival crawl.

Gearing

Gear for the maximum, not the average. A compact 34-tooth chainring paired with a 34×32 cassette is the sensible minimum here, and given the 31.92% pitches, 34×34 is the smarter call for most riders — the extra sprocket is the difference between spinning through the steep ramps and grinding to a standstill. On a climb with 1010 m of net gain and this much sustained load above 8%, a low gear you rarely need beats a high gear you desperately wish you had. Fit the widest-range cassette your derailleur allows.

Summary

The Collado de Prao Poyo o del Miradero is a genuine HC test: long, relentlessly steep, and topped by ramps that few climbs can match. Pace it to your threshold, gear it for the wall, and respect the full 1010 m of climbing from bottom to top.

Length: 12.1 km
Average gradient: 8.33%
Max gradient: 31.92%
Start: 950 m
Summit: 1960 m
Net gain: 1010 m
Total ascent: 941 m
Category: HC