Col de l'Œillon

Overview

Col de l'Œillon is a category 1 climb in France, running 11.9 km from a start elevation of 389 m to a summit at 1,238 m. Over that distance it delivers 849 m of net elevation gain at an average gradient of 7.12%. That combination of length and steepness puts it firmly in serious-climb territory: long enough to demand real pacing discipline, steep enough that there is no coasting your way to the top.

The number to pay attention to is the gap between net gain and total ascent. You climb 849 m net, but the profile actually racks up 1,032 m of total ascent — roughly 183 m of extra climbing hidden in dips and false descents. That means the road gives some height back along the way, and every metre it returns is a metre you have to earn again. Your legs feel the 1,032 m, not the 849 m, so plan your effort around the larger figure.

How the Gradient Unfolds

The 7.12% average is an accounting trick. Because the climb undulates, the average is dragged down by the flatter and downhill stretches, which means the pitches that actually climb are steeper than 7.12% to compensate. The headline number is the steepest ramp at 21.79% — a wall that will spike your heart rate and force you out of any rhythm you've built.

Here is what to expect across the profile:

• Flatter and recovery sections where the road eases or briefly tips downhill — use them, don't attack them
• Repeated short climbs that regain the height you just lost, each one a fresh effort
• A steepest ramp of 21.79% that demands your lowest gear and a deliberate, seated grind

Pacing Notes

On a smooth, steady climb you can hold even power and let speed take care of itself. Col de l'Œillon is not that climb. With 183 m of undulation on top of the net gain, chasing an even speed will blow you up on the steep ramps and waste the flatter bits. Anchor your effort to even power based on your sustainable power output instead, and let your speed rise and fall with the terrain. On the pitches toward 21.79%, allow a brief surge above target rather than grinding to a standstill; on the recovery sections, ease off and let the numbers settle. If you don't know your threshold, run the FTP estimator before you go so you're pacing to a real number, not a guess.

Gearing

Gearing here is dictated by the steepest ramp, not the average. At 21.79% you need a bailout gear that lets you keep a workable cadence seated. Run a compact (34-tooth inner) or sub-compact chainset paired with a wide-range cassette — something like a 34×32 or 34×34 at the low end. If your current setup tops out at a smaller sprocket, you'll be mashing a big gear on the wall and paying for it long before the summit. Check your chainset and cassette before the ride, and confirm the derailleur actually handles the largest cog.

Summary

• Length: 11.9 km
• Average gradient: 7.12%
• Maximum gradient: 21.79%
• Net elevation gain: 849 m
• Total ascent: 1,032 m
• Category: 1

Col de l'Œillon rewards riders who respect its undulation: pace to power, gear for the 21.79% wall, and treat the 1,032 m of total ascent as the real workload. Do that, and the summit at 1,238 m comes to you.