Col des Lèques

What the Col des Lèques Is

The Col des Lèques is a Category 3 climb in France, running 6.9 km with 506 metres of total ascent. Starting at 811 metres and topping out at 1,148 metres, it is not a monster by alpine standards — but its maximum gradient of 19.77% means it carries a serious sting that the average figure of 4.92% does nothing to warn you about.

That gap between average and maximum is the defining characteristic of this climb. A sub-5% mean sounds manageable for almost any trained rider; a near-20% ramp is a different conversation entirely.

How the Gradient Unfolds

The 506-metre total ascent spread across 6.9 km confirms that the Col des Lèques is not uniformly steep. Sections of relatively gentle gradient — likely well below the 4.92% average — are interspersed with at least one violent pitch that reaches 19.77%. This profile is typical of climbs that follow old road alignments through irregular terrain: long traverses punctuated by short, brutal ramps where the road cuts directly up a slope rather than switchbacking around it.

The practical consequence: do not treat this as a climb where you can lock into one power output and hold it to the summit. The gradient variance demands active effort management.

Pacing Notes

Treat the average gradient as a planning floor, not a target. Riding the Col des Lèques at a pace calibrated to 4.92% will leave you under-geared and over-extended when the road kicks toward 19.77%. Plan for the spikes.

• Before the steep sections: Keep power controlled. If you arrive at the sharp ramps already deep into your FTP, the steepest pitches will force you to either blow up or grind to a near-stop.
• On the maximum-gradient ramp: At close to 20%, staying seated becomes a strength and traction question as much as an aerobic one. Riders with a compact chainset or wide-range cassette will manage cadence better here. A 34×32 or equivalent gives you options; arriving in a 39×25 does not.
• After the steep sections: Resist the temptation to immediately push hard. These ramps create localised lactate spikes. Give yourself 30–60 seconds at reduced effort before resuming target pace toward the summit.

Gearing Recommendations

Given the 19.77% maximum gradient, treat gearing the same way you would for a climb with a wall section. If you are unsure what gearing suits your power-to-weight ratio and the gradients you will face, use the FTP estimator to anchor your numbers before selecting a cassette.

• Compact or sub-compact crankset (50/34 or 46/30) is strongly advisable for riders who are not confident on sustained double-digit gradients.
• Cassette: An 11-32 or 11-34 is sensible. An 11-28 is marginal.
• Road bike riders: If your bike is set up for flatter terrain, consider the 19.77% spike a genuine test. A 28-tooth small ring paired with a 28-tooth sprocket will give a gear ratio of 1:1 — workable, but not comfortable for most riders at that pitch.

Bottom Line

The Col des Lèques is a climb that rewards respect and punishes complacency. Its Category 3 designation and sub-5% average can lull riders into under-preparing. The 19.77% maximum gradient is the number that actually governs how you should approach it — in gearing selection, in pacing strategy, and in how you manage effort in the kilometres leading into the hardest section.