Colle Ben Mulè

Overview

Colle Ben Mulè is one of those climbs whose numbers tell you almost everything before you turn a pedal. Six kilometres long, it lifts you from a start elevation of 403 m to a summit of 1329 m — a net gain of 926 m. Squeeze that vertical into so short a distance and you arrive at an average gradient of 15.42%, with the road spiking to a savage 32% at its worst. Add up the rises and falls along the way and the total ascent lands at 844 m of genuine climbing metres. This is a hors catégorie (HC) effort, the hardest classification on the scale, and the profile earns every letter of it.

How the Gradient Unfolds

There is very little hiding on a road that averages 15.42% over its full 6 km. The defining feature here is relentlessness: even the easier sections sit well into double digits, so there is no recovery flat to shake your legs out. The peaks in the profile matter most. When the gradient rears up toward 32% — more than double the average — momentum evaporates and the climb becomes a battle of raw torque against gravity. Because the total ascent of 844 m sits below the 926 m net gain, the route trends consistently upward with only minor easing rather than any real descent to break the rhythm. Expect the pitch to swing between merely hard and outright brutal, again and again, all the way to 1329 m.

Pacing Notes

On a wall this steep, pacing is less about elegance and more about survival. Your FTP is the number that governs how long you can hold the surges over 20%, so know it before you commit. On a 15.42% average you will spend long stretches above threshold whether you like it or not, so the goal is to bleed as little as possible into the red on the shallower ramps and save something for the 32% pitches where power spikes are unavoidable. If you are unsure of your current threshold, run the numbers first with the FTP estimator and set a ceiling you can defend across all 6 km rather than one you can only hold for two.

Gearing

Do not under-gear this climb. With a 15.42% average and a 32% maximum, most riders will want the widest ratio they can bolt on. A compact 34-tooth chainring paired with a 34×32 cassette is the sensible baseline, giving you a survivable spin on the sustained sections. But on the steepest 32% ramps, even that can feel over-geared, so a 34×34 is worth serious consideration — the extra sprocket buys precious cadence when the road tips beyond 30%. Over 926 m of net vertical, protecting your knees and keeping the cranks turning matters more than pride.

Summary

Colle Ben Mulè is a short, ferocious HC test defined by its 15.42% average and 32% maximum. Six kilometres, 926 m of net gain, and no mercy in between — respect it, gear for it, and pace it honestly.

Length: 6 km
Average gradient: 15.42%
Max gradient: 32%
Start: 403 m
Summit: 1329 m
Net gain: 926 m
Total ascent: 844 m
Category: HC