Portella di Mandarini

Overview

Portella di Mandarini is an HC climb, the hardest classification on the scale before you reach 1, 2, 3, and 4. Over just 6.6 km it averages a brutal 13.21%, dragging you from a start elevation of 338 m all the way up to a 1215 m summit. That is a net elevation gain of 877 m packed into a road that never lets you settle. With total ascent measured at 830 m and pitches spiking to 17.06%, this is a climb defined by relentless steepness rather than length. There is nowhere to hide and almost nowhere to recover.

How the Gradient Unfolds

The defining feature here is that the average and the maximum are close together: 13.21% mean against a 17.06% peak. That narrow spread tells you the entire climb sits in a steep band, so you rarely drop into easy grades between the hard ramps. From the 338 m base the road tilts up immediately and holds double-digit gradients almost continuously toward the 1215 m top. The steepest sections, at 17.06%, are only a few percent above the average, which means the "hard" parts feel like a slight intensification of an already savage baseline rather than isolated walls. Expect a wall-like profile where the gradient hovers stubbornly in the mid-teens for kilometre after kilometre.

Pacing Notes

On a climb this steep, pacing is everything. With a sustained 13.21% average over 6.6 km, the effort will push most riders toward or beyond their threshold for the full duration, so treat your FTP as the ceiling you must not blow through in the opening kilometre. The temptation is to attack the first ramp off the 338 m base; resist it, because there is no flat section ahead to recover. Settle into a rhythm you can hold for the entire 877 m of climbing, and accept that even a steady effort will feel maximal near the 17.06% pitches. If you are unsure where your sustainable power sits, run the numbers first with the FTP estimator and set a hard cap before the road bites.

Gearing

Do not underestimate the gearing demand on a 13.21% average with 17.06% maximum pitches. A compact 34-tooth chainring is the starting point, and the cassette is where you buy survival. A 34×32 is the absolute minimum most riders should consider here, and even strong climbers will be grinding at the low end of it on the steepest ramps. For anyone not racing, or anyone who wants to protect their knees over 6.6 km of unrelenting gradient, step up to a 34×34 for a genuine bailout gear. On a climb this steep, an extra sprocket is the difference between spinning and stalling.

Summary

Portella di Mandarini is a pure test of climbing legs: short, savage, and consistently steep from base to summit with no respite. Come with low gears, a disciplined pacing plan, and respect for a gradient that barely dips below the mid-teens.

Length: 6.6 km
Average gradient: 13.21%
Max gradient: 17.06%
Start: 338 m
Summit: 1215 m
Net gain: 877 m
Total ascent: 830 m
Category: HC