Col de Larrieu

Overview

Col de Larrieu is a Category 3 climb in France stretching 9.4 km from base to summit. The net elevation gain is 336 m — modest on paper — but the total ascent of 427 m tells the real story: the road undulates enough to add meaningful extra climbing on top of what the start-to-finish numbers suggest. The average gradient of 3.59% is gentle by alpine standards, yet a maximum gradient of 15.14% confirms this is not a uniform grind. Expect at least one genuinely steep ramp that will punish anyone who has spent their matches too early.

How the Gradient Unfolds

With a 91 m gap between net elevation gain (336 m) and total ascent (427 m), Col de Larrieu almost certainly features one or more dips or false flats that reset the legs before the road kicks again. That pattern is important for pacing strategy:

• Lower slopes: With the road starting at 386 m and the average gradient well under 4%, the early kilometres are likely to feel straightforward. Resist the temptation to push into the red here — the kick to 15% is waiting.
• Mid-climb undulations: The difference between net and total ascent suggests sections where the road eases or briefly descends. Use these to recover, not to accelerate.
• Steep ramp(s): The 15.14% maximum is a sharp spike relative to the 3.59% average. It is likely concentrated in a short section rather than sustained, but even a short wall at that gradient demands a gear you can actually turn over. If you are already breathing hard, it will feel much longer than it is.

Pacing Notes

Because the average gradient is low, many riders will approach Col de Larrieu without treating it as a serious pacing challenge. That is a mistake if the 15% ramp catches you off guard.

• Set a ceiling early. Ride the opening kilometres well within your FTP. A target of 75–80% of FTP for the shallow sections keeps you fresh for the steep pitch.
• Identify the ramp before you ride. If you have access to a gradient plot, locate the 15% section so you know when to shift and when to brace. Arriving at a 15% wall already in too large a gear is a reliable way to blow up or be forced to a standstill.
• Gearing: A compact or semi-compact chainset with a 32 or 34-tooth cassette sprocket is sensible insurance for the maximum gradient sections, especially for heavier riders or those carrying fatigue from a longer day in the saddle. Use the FTP estimator to gauge what gear you realistically need at your target power output on a 15% gradient.
• The descent within the climb: If the road dips mid-climb, do not coast through it passively. Spin gently, breathe, and prepare to re-engage — but avoid surging out of it, which spikes heart rate before the next ramp.

Summit

The summit sits at 722 m. For a Category 3 classification, the climb is neither a throwaway nor a leg-breaker — it sits squarely in the range where poor pacing costs more time than most riders expect. Treat it with the same structure you would apply to any punchy, irregular climb rather than a long steady grind.