Passaggio dell'Adamello

Overview

Passaggio dell'Adamello is a hors catégorie climb that earns its rating without ambiguity. Over 17.9 km it averages 8.89%, hauling you from a start elevation of 754 m to a 2343 m summit. That is a net gain of 1589 m — thin-air territory where the altitude itself starts taxing your legs. The total ascent of 1536 m confirms the road climbs almost relentlessly, giving back very little along the way. For a climb of this length, an average approaching 9% is brutal: there is no flat run-in inflating the distance and no easy false-flat to hide behind. From the first ramp to the last, this is a sustained HC effort that rewards patience and punishes anyone who goes out hot.

How the Gradient Unfolds

The headline number is the 8.89% average, but averages lie on a climb like this. The 36.3% max gradient tells the real story: somewhere on the mountain the road kicks up into a wall steep enough to stall an unprepared rider mid-pedal-stroke. Expect the gradient to swing hard around that 8.89% mean — long stretches sitting near or above 9%, punctuated by savage pitches that spike toward that 36.3% ceiling. Because the climb never truly relents across its 17.9 km, you rarely get recovery. The 1589 m of net gain against 1536 m of total ascent shows the profile is almost monotonically upward, so plan to meter your effort as if every kilometre is uphill — because it very nearly is.

Pacing Notes

Discipline wins here. On a 17.9 km climb averaging 8.89%, the temptation to chase the early ramps will cost you dearly near the 2343 m summit, where altitude compounds fatigue. Anchor your effort to your FTP and hold something in reserve for the steepest pitches, which climb toward 36.3% and force brief surges above threshold whether you like it or not. A sensible target is a steady sub-threshold pace for the sustained sections, spending your matches only where the gradient leaves no choice. If you are unsure of your number, run the FTP estimator before you commit to a pacing plan. Over 1589 m of net climbing, going 5% too hard in the first third can turn the final kilometres into a survival crawl.

Gearing

Gear for the wall, not the average. With an 8.89% mean over 17.9 km and spikes to 36.3%, you want the smallest gears you can fit. A 34×32 is the minimum I would take onto this climb, and even then the steepest pitches will have you grinding. For most riders a 34×34 is the smarter choice, giving you a lower floor to spin the savage ramps without wrenching your cadence to a standstill. If your frame and derailleur allow anything easier, use it — over 1536 m of ascent to a 2343 m summit, protecting your knees and holding cadence matters far more than saving a few grams.

Summary

Passaggio dell'Adamello is a genuine HC test: long, steep, high, and unforgiving from the 754 m start to the 2343 m top. Pace it conservatively, gear it generously, and respect the 36.3% pitches, and you will reach the summit with dignity intact.

Length: 17.9 km
Average gradient: 8.89%
Max gradient: 36.3%
Start: 754 m
Summit: 2343 m
Net gain: 1589 m
Total ascent: 1536 m
Category: HC