Pas du Boeuf

Pas du Boeuf cycling climb profile

Pas du Boeuf is a pure climbing test on paper, and the numbers explain why it has to be ridden with discipline. The climb is 18.2 km long, averages 11.99%, starts at 628 m, and tops out at 2815 m. That means the road gains 2187 m between start and summit, which is why this sits firmly in HC territory rather than simply being a hard alpine ascent.

The defining feature is not just the average gradient. It is what that average implies across the full length. A climb can only average 11.99% over 18.2 km if there is very little easy terrain to reset the legs. Even before accounting for the maximum gradient of 29.54%, the baseline effort is already high enough that most riders will spend long periods close to sustainable climbing intensity.

How the gradient shapes the ride

From the bottom, the key mistake is treating Pas du Boeuf like a climb that will naturally open up later. With an average of 11.99%, the road is already asking for a low-cadence, high-torque effort unless gearing is generous. If the early pace is even slightly too ambitious, the cost compounds quickly because the climb is long enough for small pacing errors to become decisive.

The maximum gradient of 29.54% changes the tactical picture. Those ramps are not sections to attack unless the rider has a large margin. They are moments to survive efficiently. On gradients that steep, speed drops, torque demand rises sharply, and any attempt to hold a normal rhythm can push the effort above threshold before the rider realizes it. The practical goal is to keep forward momentum without turning the steepest pitches into repeated anaerobic efforts.

Pacing and gearing notes

Ride this climb from the bottom as a controlled endurance-to-threshold effort, not as a sequence of short ramps. The length and average gradient make it a climb where restraint early has a real payoff near the summit.

A few practical rules matter here:

• Use the easiest climbing gear available. Pas du Boeuf is not a climb where standard road gearing leaves much room for error.
• Keep cadence as smooth as the gradient allows, but accept that the steepest sections will force a lower rhythm.
• Stay seated where possible to manage traction and muscular load, then stand briefly only to clear the hardest pitches or change muscle recruitment.
• Avoid chasing speed on the lower slopes. On a climb averaging 11.99%, perceived slowness is not a sign of poor pacing. It is the terrain doing what the terrain does.

For pacing by power, anchor the effort to sustainable climbing output rather than short-term motivation. If you use /glossary/ftp as a reference point, the opening should feel deliberately conservative, because the 18.2 km length and 2187 m gain leave very little tolerance for overreaching. The riders who climb Pas du Boeuf well will not be the ones who look fastest at the bottom. They will be the ones still able to turn the gear cleanly when the altitude, accumulated torque, and steep ramps are all working against them.