Forcella del Portonat

Overview

Forcella del Portonat is a category-1 climb that asks a serious question of your legs across a full 12 km. From a start elevation of 292 m it lifts you to a summit of 1183 m, a net gain of 891 m, while the road actually stacks up 848 m of total ascent along the way. The headline number is an average gradient of 7.44%, which already places it in the demanding tier, but averages hide the story here. With a maximum pitch of 31.6% lurking somewhere in the middle of those kilometres, this is a climb that rewards restraint early and punishes anyone who spends their matches on the flatter opening slopes.

How the Gradient Unfolds

The shape matters more than the average on Portonat. Twelve kilometres at 7.44% would be honest but manageable if the gradient were smooth; it is not. The gap between the 7.44% average and the 31.6% maximum tells you the road pulses rather than settles. Expect stretches that sit near or just below the average, interrupted by short, brutal walls where the surface kicks toward that 31.6% ceiling. Because net gain (891 m) exceeds total ascent (848 m) only marginally, there is very little false-flat or descending relief to recover on — once you are climbing, you keep climbing. Treat every eased section as a chance to breathe before the next ramp, not as a place to accelerate.

Pacing Notes

The single most useful lever on a climb like this is your FTP. Twelve kilometres at 7.44% is long enough that your sustainable power, not your top-end punch, decides the outcome. Set a target effort you can hold for the full ascent and refuse to chase the gradient on the steep pitches — surging into a 31.6% wall at threshold empties the tank fast, and there is 892 m of vertical still to give. If you do not know your number, run it through the FTP estimator first, then ride the flatter opening at a touch below threshold and accept that the steepest ramps will spike your power briefly no matter what. Over-under discipline, not heroics, gets you to 1183 m.

Gearing

Do not under-gear this one. With ramps reaching 31.6% and 891 m to grind out over 12 km, a compact chainset paired with a wide cassette is the sensible floor. A 34×32 is the minimum I would recommend for most riders, and it will feel adequate on the average slopes. But for the steepest walls — and to protect your knees and your pacing over the full climb — a 34×34 gives you the extra spin you will want when the road stands up. If your bike accepts it, err toward the easier ratio; nobody regrets a bailout gear on a 31.6% pitch.

Summary

Forcella del Portonat is a category-1 test defined by its steep, uneven pitches rather than a relentless uniform grade. Pace to your FTP, gear low, and respect the 31.6% ramp, and the 891 m of climbing to 1183 m becomes a rewarding day out.

Length: 12 km
Average gradient: 7.44%
Max gradient: 31.6%
Start: 292 m
Summit: 1183 m
Net gain: 891 m
Total ascent: 848 m
Category: 1