Colletto Disgrazia

Overview

Colletto Disgrazia is a hors catégorie (HC) climb, the hardest rating a road ascent can carry. It runs for 24.8 km, starting at 312 m and topping out at 1954 m. That's a net elevation gain of 1642 m, with 1619 m of total ascent once you account for every metre gained across the climb. The average gradient sits at 6.62%, which sounds civilised until you see the 18.84% maximum lurking in the profile. This is a long, sustained effort where the sheer duration does as much damage as any single ramp.

How the Gradient Unfolds

At 24.8 km, this is an endurance climb first and a steepness challenge second — but it is both. A 6.62% average over nearly 25 kilometres means there is almost no genuine recovery; the road keeps tilting upward relentlessly. The gap between the 6.62% average and the 18.84% maximum tells you the story: expect long stretches around the average punctuated by pitches more than twice as steep. When the gradient more than doubles, cadence collapses and your effort spikes hard. Because the climb gains 1642 m net but records 1619 m of total ascent, the profile is overwhelmingly one-directional — you climb, and you keep climbing, with no meaningful descents to break the rhythm.

Pacing Notes

On a climb this long, discipline wins. Anchor your effort to your FTP rather than to how you feel in the opening kilometres, because the 18.84% ramps late in the climb will punish anyone who burned matches early. Ride the 6.62% sections a touch below threshold and save headroom for the steep pitches, where power surges are unavoidable. If you don't have a reliable threshold figure, run your numbers through the FTP estimator before you go — a good estimate turns 24.8 km of guesswork into a paced, repeatable effort. Aim to arrive at the steepest ramps with something left, not clinging on.

Gearing

Gear for the 18.84% maximum, not the 6.62% average — the steep pitches decide what you need. A compact 34-tooth front paired with a wide-range cassette is the sensible baseline. A 34×32 will get most strong riders over the top, but on a climb that keeps grinding upward for 24.8 km with ramps near 18.84%, the extra security of a 34×34 is worth having. That single extra sprocket lets you spin the steep sections instead of grinding them, protecting your legs across an ascent that gains 1642 m. If your setup allows even lower, take it — nobody has ever regretted an easier gear on an HC climb.

Summary

Colletto Disgrazia is a proper HC test: 24.8 km, an average of 6.62%, a summit at 1954 m, and pitches up to 18.84%. Pace it against your FTP, gear low, and respect the 1642 m of net gain from the very first pedal stroke.

Length: 24.8 km
Average gradient: 6.62%
Max gradient: 18.84%
Start: 312 m
Summit: 1954 m
Net gain: 1642 m
Total ascent: 1619 m
Category: HC