Col Collon

Col Collon cycling climb profile

Col Collon is a Category 1 climb in CH that asks for patience more than aggression. On paper, 39.4 km at 3.79% looks controlled, but the important number is the elevation gain: 1,494 metres from a start elevation of 558 metres to a summit elevation of 2,052 metres. This is not a short climb with one decisive pitch. It is a long upward drag where pacing errors compound slowly and become expensive late.

The total ascent is 1,504 metres, only slightly higher than the net elevation gain. That tells you the profile trends upward with very little relief. Even if the average gradient stays under 4%, the climb keeps taking energy because there is not much free recovery built into the numbers.

How the gradient unfolds

The average gradient is the main trap. A 3.79% average over nearly 40 km suggests a climb that can feel deceptively rideable early, especially if you arrive fresh or in a group. But with a maximum gradient of 9.3%, the road clearly has sharper ramps inside the broader steady profile.

That combination matters. A long climb with a modest average and near-10% maximum gradient rewards riders who avoid chasing speed every time the road eases. The easier sections are where you should reset cadence, keep breathing under control, and prepare for the steeper pitches. If you ride the first half as if the average gradient is the whole story, the later ramps will force you above threshold when you least want it.

Pacing strategy

Treat Col Collon as a sustained aerobic climb with intermittent pressure points. The correct pacing model is not to attack the steepest ramps, but to cap them. Keep the bulk of the effort below /glossary/ftp, then allow only short, controlled rises when the gradient approaches its maximum.

A good ride here should feel almost too restrained at the bottom. Over 39.4 km, a small overreach early can turn into a long fade before the summit. The climb’s low average makes it tempting to push a bigger gear, but the accumulated gain says otherwise. Aim for a smooth power ceiling rather than a speed target.

Gearing notes

Use gearing that lets you stay seated and maintain cadence when the road kicks toward 9.3%. You do not need a survival setup for repeated double-digit gradients, based on the listed maximum, but you do need enough range to avoid grinding late in the climb.

If you are riding by power, set a conservative cap and stick to it. If you are riding by feel, the check is simple: the first long section should feel controlled enough that you could still respond when the steeper ramps arrive. Col Collon is won by restraint, not by forcing the pace from the valley.