Col du Parpaillon

Overview

The Col du Parpaillon is one of those climbs where the numbers tell you almost everything you need to know before you turn a pedal. It runs 8.2 km from a start elevation of 1688 m to a summit at 2779 m — a net gain of 1091 m over a distance that most riders would consider short. Do that arithmetic and you land on an average gradient of 13.26%, which is not a rolling road or a steady drag but a relentless wall. Rated HC (hors catégorie, the hardest classification above categories 1 through 4), the Parpaillon earns that label not through length but through sheer, unbroken steepness at altitude.

How the Gradient Unfolds

An 8.2 km climb that averages 13.26% leaves little room for recovery. Where many HC climbs blend flatter valley approaches with brutal ramps, the Parpaillon's total ascent of 1388 m against a net gain of 1091 m tells you there is a little rolling terrain baked in — roughly 297 m of extra climbing hidden in dips and rises that you pay for twice. In practice this means the true pitches are steeper than the 13.26% average suggests, because the road has to claw back elevation it briefly surrenders. Starting at 1688 m and topping out at 2779 m, the entire effort sits high, so the thin air compounds every ramp. Expect the gradient to sit stubbornly in the low-to-mid teens for long stretches with no genuine flat to shake out your legs.

Pacing Notes

On a climb this steep, pacing is everything — go out too hard on the opening ramps and the final third at altitude will unravel you. Anchor your effort to a percentage of your FTP rather than to speed, since your pace over 8.2 km at 13.26% will feel painfully slow no matter how strong you are. Most riders should target a sustainable tempo-to-threshold effort and hold it, accepting that the 1091 m of net gain will take time. If you are unsure of your threshold number, run the FTP estimator first and build your target power band from there. The 2779 m summit means aerobic capacity fades as you climb, so leave a small reserve for the highest, thinnest section.

Gearing

Do not under-gear this climb. At a sustained 13.26% over 8.2 km, a compact chainring with a wide-range cassette is the minimum sensible setup. A 34×32 will get most fit riders to the top, but on a wall this steep at 2779 m altitude, the extra margin of a 34×34 is well worth carrying — it lets you spin rather than grind, protecting your knees and your matches for the 1091 m of climbing ahead. If your bike allows an even easier ratio, use it. Nobody has ever regretted an easier gear on the Parpaillon.

Summary

The Col du Parpaillon is a compact, savage HC climb: 8.2 km, 13.26% average, and 1091 m of net gain topping out at 2779 m. Respect the gradient, gear low, pace to power, and it becomes a summit worth every meter.

Length: 8.2 km
Average gradient: 13.26%
Max gradient: n/a
Start: 1688 m
Summit: 2779 m
Net gain: 1091 m
Total ascent: 1388 m
Category: HC