Col de la Rousse

Col de la Rousse: Climb Profile & Pacing Notes

Col de la Rousse is an HC-rated ascent in France that earns its classification honestly. Over 13.2 km, it averages 10.3% — a gradient that sits firmly in the territory where poor pacing becomes very expensive, very quickly. With 1,364 m of net elevation gain from start to summit and a total ascent of 2,174 m across the full route, this is not a climb that offers hiding places.

The Numbers at a Glance

• Length: 13.2 km
• Average gradient: 10.3%
• Maximum gradient: 54.18%
• Net elevation gain: 1,364 m
• Total ascent: 2,174 m
• Category: HC (Hors Catégorie)

The gap between net elevation gain (1,364 m) and total ascent (2,174 m) tells you something important: there is meaningful up-and-down terrain embedded in this climb. You are not simply grinding a steady ramp. Expect sections where the road briefly relents or dips, only to reassert itself — often harder than before.

How the Gradient Unfolds

The climb begins at 769 m and finishes at 2,133 m. That 1,364 m of net gain packed into 13.2 km produces that 10.3% average, but the maximum recorded gradient of 54.18% is the detail that demands respect. A pitch at that angle is less a cycling gradient and more a wall — likely a short, sharp ramp rather than a sustained section, but it will spike heart rate and force an immediate gear decision. Hit it too fast and you risk blowing up on either side of it; hit it without a low enough gear and you stall.

At 10.3% average, the bulk of this climb sits in the range where your FTP sets the ceiling for sustainable effort. Riding above threshold for extended stretches on a 13.2 km climb is a losing strategy. The severe maximum gradient confirms that the road is not linear — there are punishing spikes that require reactive gearing rather than a locked-in cadence.

Pacing Strategy

Start conservatively. On any climb averaging above 10%, the opening kilometers feel manageable precisely because fresh legs mask early over-exertion. Resist that. Set a power or perceived effort ceiling based on your threshold and hold it.

Anticipate gradient spikes. With a maximum of 54.18%, at least one section of this road crosses into near-unrideable territory for most gearing setups. Before the climb, confirm your lowest available gear ratio and know that you may need it suddenly. Spinning out is not a concern here — stalling or being forced to unclip is the real risk.

Use the dips. The difference between net and total ascent means descents or flat sections exist within the climb. Use these to recover — lower your effort, spin the legs, and prepare for the next kick. Don't accelerate through them in an attempt to bank time; the climb will take it back.

Manage the back half. At 13.2 km, this is a long sustained effort. Riders who go too deep in the first 6–7 km will feel the top third acutely. If you have access to climb segment data, use it to identify where the steepest sustained sections appear and plan your effort budget accordingly. Use the FTP Estimator to calibrate your target power before attempting the full ascent.

Gearing Notes

For a climb with a 10.3% average and isolated ramps approaching 54%, a compact chainset (50/34 or smaller) paired with a wide-range cassette (32t or 34t) is the practical minimum for most riders. Anything more aggressive risks a forced dismount on the steepest pitches. If you are riding a standard double, be realistic about where your limits are before the summit.

Col de la Rousse is not a climb for tempo riding. It is an HC ascent that rewards patience, honest self-assessment, and appropriate equipment.