Col des Posettes

Overview

The Col des Posettes is a short climb only by the clock. Across 8 km the road climbs at an average of 12.95%, lifting you from a start elevation of 493 m to a summit of 1532 m. That is a net elevation gain of 1039 m packed into a distance most riders would consider a warm-up on gentler terrain. Rated HC — hors catégorie, the hardest classification above categories 1 through 4 — it earns the label honestly. There is no long valley approach hidden inside the number, no flat kilometre to recover on. The gradient simply sits high and stays there, and the total ascent of 1020 m confirms there is almost nothing here but climbing.

How the Gradient Unfolds

A 12.95% average is the headline, but averages flatten the story. On a climb this steep, the mean is punishing on its own, yet the road spikes to a 25% maximum gradient — roughly double the average. That means stretches where the pitch nearly doubles the effort you have already been holding. Expect the difficulty to arrive early and never fully release. Because the net gain of 1039 m and the total ascent of 1020 m are so close, there is little false flat or descending to break the rhythm: what goes up mostly keeps going up. Plan your effort around the assumption that any ramp could steepen toward that 25% wall without warning.

Pacing Notes

On a wall like this, restraint in the first 2 to 3 km decides everything. With an average of 12.95%, going even slightly too hard early leaves nothing for the steepest ramps. Anchor your pacing to a percentage of your FTP: most riders should sit just below threshold on the sustained sections and accept short surges above it only when the 25% pitches force the issue. If you do not know your threshold, run your numbers through the FTP estimator before you tackle this — guessing your ceiling on an 8 km HC climb is how good days unravel. Keep your effort as even as the terrain allows, and save a small reserve for the summit approach.

Gearing

Do not under-gear this one. With a 12.95% average and 25% maximum, you want the widest range you can fit. A compact 34-tooth front paired with at least a 32-tooth rear — a 34×32 — is the sensible floor for strong climbers, and even they will be grinding. Most riders will be far happier on a 34×34, and anyone carrying fatigue or extra weight should consider going wider still. The goal is to keep cadence turning on the steepest ramps rather than lurching into a muscular grind that burns matches you cannot afford over 8 km.

Summary

The Col des Posettes is a compact, relentless HC test: 8 km that never lets the gradient dip, topping out with 1039 m of net climbing. Gear low, pace with discipline, and respect the ramps.

Length: 8 km
Average gradient: 12.95%
Max gradient: 25%
Start: 493 m
Summit: 1532 m
Net gain: 1039 m
Total ascent: 1020 m
Category: HC