Coll d'Ares

Overview

Coll d'Ares is a long category 1 climb that rewards patience over punch. Over 22.6 km it lifts you from a start at 375 m to a summit of 1494 m, a net gain of 1119 m. The average gradient reads a modest 4.96%, but that headline number hides the shape of the effort: with a total ascent of 1138 m against 1119 m of net gain, there is almost no wasted descending here. Nearly every metre you climb, you keep. That makes this a relentless, steady-state ascent rather than a series of walls and recoveries.

How the Gradient Unfolds

At 4.96% average, Coll d'Ares sits in the sweet spot where the road never feels flat but rarely feels desperate. The max gradient of 11.34% is more than double the average, so the difficulty is not evenly spread. Expect long stretches close to the mean punctuated by steeper ramps that briefly load the legs. Because total ascent (1138 m) exceeds net gain (1119 m) by only a small margin, there are barely any false-flat rollers to break the rhythm — the gradient simply keeps ticking upward. The challenge is duration: holding a sustainable effort for 22.6 km without letting the steeper pitches spike you into the red.

Pacing Notes

On a climb this long, the winning strategy is discipline. Aim to ride the bulk of the ascent at or just below your threshold, treating the 11.34% ramps as brief overshoots rather than efforts you chase. Your FTP is the anchor here: settle into a power that you know you can hold for well over an hour, since 22.6 km at 4.96% will keep most riders working for a long time. If you are not sure where your ceiling sits, run the numbers through the FTP estimator before you commit to a pace. Start conservatively — the early kilometres feel easy at 4.96%, and the temptation to bank time is exactly what blows up on the upper slopes.

Gearing

With 1119 m of climbing to absorb and pitches touching 11.34%, gearing is about protecting your cadence deep into the effort. A compact chainring paired with a wide cassette is the right call. A 34×32 will handle the steady 4.96% sections comfortably and gives you enough range for most of the steeper ramps. If you climb at a lower cadence, carry extra fatigue, or simply want insurance for the 11.34% max, step up to a 34×34. That final sprocket keeps your legs spinning when the gradient bites late in the 22.6 km, which matters far more here than raw top-end speed.

Summary

Coll d'Ares is a test of sustained aerobic strength: long, consistent, and almost entirely uphill from bottom to top. Pace it by your threshold, gear it to spin, and let the steady 4.96% do the work rather than fighting it. Get the rhythm right and the summit at 1494 m arrives as a reward rather than a rescue.

Length: 22.6 km
Average gradient: 4.96%
Max gradient: 11.34%
Start: 375 m
Summit: 1494 m
Net gain: 1119 m
Total ascent: 1138 m
Category: 1