Col des Croix

Overview

Col des Croix sits in the Category 3 bracket, which can lull riders into underestimating it. The headline numbers — 6.1 km at a 4.47% average — suggest a manageable effort. The 18.55% maximum gradient tells a different story. This is a climb that rewards patience and punishes anyone who treats the average as representative of what the road actually does.

The ascent gains 483 m of elevation across those 6.1 km, rising from 413 m at the base to a summit at 684 m. That's a compact climb with a moderate total load, but the gradient variance is high enough to demand a specific approach.

How the Gradient Unfolds

With an average of 4.47% across 6.1 km, large sections of Col des Croix are gentler than the overall figure implies — necessary to balance out wherever the road hits its 18.55% ceiling. Expect a rhythm-breaking ramp or series of ramps somewhere on the profile that spikes well above double the average gradient.

What to watch for

• Mellow entry or exit sections: An 18.55% maximum dragging an average down to 4.47% suggests significant flat or near-flat terrain on the climb. Use these sections for recovery, not acceleration.
• The steep ramp(s): At nearly four times the average gradient, the maximum pitch is severe. On a road bike, anything above 15% demands either a compact chainset or a wide-range cassette. At 18.55%, most riders will want a 32T or larger cog available.
• False flats: The gradient variance on this climb makes it likely that sections feel easier than they are. Riders who surge on the easier pitches may find their legs depleted before the steepest section arrives.

Pacing Notes

Because the average gradient here is moderate, the temptation is to ride above threshold early and rely on the easier sections to recover. That strategy works until the road tilts past 15%. At that point, anyone already carrying fatigue will be grinding.

A better approach:

1. Ride to power, not feel. On a climb with this much gradient variation, perceived effort swings wildly. If you have a power meter, target a power output tied to your FTP rather than chasing a constant cadence or heart rate.
2. Stay seated through the steep sections where possible. Out-of-saddle efforts on gradients approaching 18% are expensive. Unless you're sprinting for a segment or KOM, conserve by staying seated and accepting a lower cadence.
3. Gear selection before the ramp. Shift down before the gradient spikes, not during. Shifting under load on steep pitches accelerates chain and cassette wear and risks a dropped chain.
4. Don't bury yourself on the easier sections. Treat flatter stretches as active recovery, particularly if you haven't yet hit the climb's hardest pitch.

Not sure where your FTP stands before attempting this? The FTP Estimator can give you a working number to pace against.

Gearing Recommendation

For the 18.55% maximum gradient, a compact crankset (50/34) paired with an 11-32 or 11-34 cassette is the practical floor for most riders. Stronger climbers on a standard crankset should still carry a 28T minimum at the rear. Underestimating the steepness of the maximum pitch on a climb that averages only 4.47% is a common mistake — the road earns its reputation on those short, sharp walls.

Summary

Col des Croix is a Category 3 climb that requires more respect than its average gradient suggests. Six kilometres is short enough that the total energy cost is manageable, but the 18.55% maximum pitch is steep enough to crack a rider who hasn't paced the earlier sections conservatively. Treat the gentle sections as recovery, gear low enough to stay seated on the ramps, and ride to a power target derived from your FTP.