Col d'Anterne cycling climb profile
Col d'Anterne is an HC climb in France that asks a simple question: can you keep producing controlled power for a long time while still having a gear left for the steepest ramps. The headline numbers are enough to frame the effort. From a start elevation of 546 m to a summit elevation of 2249 m, the climb rises 1703 m over 21.2 km at an average gradient of 8.04%.
That combination matters more than any single pitch. A climb this long at just over 8% average is not a punchy ascent where you can bluff your way through on repeated surges. It is a sustained aerobic load, and the cost of going too hard early compounds quickly. The 22.57% maximum gradient then adds a second problem: even if the average is manageable on paper, there are sections steep enough to force low cadence, high torque, and sharp spikes in effort if you are not geared properly.
How the gradient rides
The available profile data supports a broad reading rather than a kilometre-by-kilometre breakdown. Bottom to summit, the defining feature is sustained climbing density. Over 21.2 km, an 8.04% average means the road does not need many extreme sections to become difficult. Any easier ground is effectively balanced by harder gradients elsewhere, and the maximum of 22.57% tells you those harder moments are severe.
The practical takeaway is that Col d'Anterne should be ridden as a long threshold-adjacent climb with anaerobic traps, not as a climb to attack repeatedly. The steepest pitches are not where the ride is won. They are where a poor pacing plan gets exposed. If you arrive at those ramps already riding above sustainable effort, cadence will collapse, torque demand will rise, and the rest of the climb becomes damage control.
Pacing and gearing notes
Start below the effort you think the average gradient deserves. On a climb with 1703 m of elevation gain, the early minutes should feel almost too controlled. If using power, anchor the opening phase around a sustainable climbing target rather than chasing speed, because speed will vary sharply with gradient. If riding by feel, keep breathing in check and avoid responding to every steepening as if it is a separate effort.
Gearing should be chosen for the maximum gradient, not the average. An 8.04% climb might tempt riders into a standard climbing setup, but a 22.57% ramp changes the requirement. You need an easy enough gear to stay seated, keep traction, and avoid grinding at a cadence that pushes you above threshold too early. If your easiest gear only feels comfortable when fresh, it is probably not low enough for this climb.
For a data-driven rider, the best strategy is restraint first, then controlled commitment. Let the length do the selection. Keep the effort smooth through the main body of the climb, protect cadence where possible, and save the hardest work for the upper part when the summit at 2249 m is close enough that an over-threshold effort has a clear payoff. For more on setting effort targets, see /glossary/ftp and /tools/ftp-estimator.