La Portella

Overview

La Portella is one of those climbs that reads like a typo until you check it twice. Over 16.8 km the road lifts you from a start elevation of 254 m to a summit at 2242 m — a net gain of 1988 m — at an average gradient of 11.87%. That average is the headline, and it is savage. Most feared alpine climbs sit somewhere in the 7% to 9% range; La Portella runs well into double digits from the bottom to the top, earning its HC (hors catégorie) rating without any argument. With a total ascent of 1936 m recorded on the profile, there is barely a metre of relief here — this is climbing in its purest, most relentless form.

How the Gradient Unfolds

The number that defines La Portella is 11.87%, and the frightening part is how little that average lies. On a climb 16.8 km long with 1988 m of net gain, the math leaves almost nowhere to hide: to average nearly 12% over that distance, the road has to stay hard the entire way. The 1936 m total ascent sitting close to the 1988 m net gain confirms it — there are no descents, no valley crossings, no false flats to spin out your legs. From the 254 m base to the 2242 m summit, the gradient simply keeps pressing. Expect the pitch to hover around and above the average for long, unbroken stretches, with the thin air of the final approach to 2242 m making the closing kilometres feel steeper still even where the road does not change.

Pacing Notes

On a climb this steep and this long, pacing is survival. Your FTP is the ceiling you must respect from the first pedal stroke — go over it early and the remaining kilometres will collect the debt with interest. On an 11.87% average, you cannot coast to recover, so ride a touch under your threshold and hold it steady rather than chasing surges. If you are unsure of your number, run the FTP estimator before you commit to a target, then plan to finish the 16.8 km with something left, because altitude near the 2242 m summit will quietly erode your power. Effort discipline beats bravado here every single time.

Gearing

Do not under-gear La Portella. At 11.87% for 16.8 km, a compact 34-tooth chainring paired with a wide cassette is the minimum sensible setup. A 34×32 is the floor for strong climbers on a good day, but most riders will be grateful for a 34×34 — and many will wish for even more. If your bike accepts a larger cassette or a smaller chainring, use it. Preserving a cadence you can sustain to 2242 m matters far more than pride; grinding a heavy gear on a slope this steep is how you blow up.

Summary

La Portella is a genuine HC test — 16.8 km that never eases, climbing from 254 m to 2242 m with 1988 m of net gain at an average that defines the whole experience. Respect the numbers, gear low, pace patiently, and it will reward you with one of the hardest summits you can ride.

Length: 16.8 km
Average gradient: 11.87%
Max gradient: n/a
Start: 254 m
Summit: 2242 m
Net gain: 1988 m
Total ascent: 1936 m
Category: HC