Passo del Fo'

Overview

Passo del Fo' is a serious day out: 18.4 km of continuous climbing at an average of 5.87%, starting from near sea level at 8 m and topping out at 1091 m. That gives a net elevation gain of 1083 m, while the odometer of vertical work — total ascent — reads 1128 m, a hint that the road doesn't rise in a single clean line. At category 1, this sits just below the hardest classification, and the length alone means you'll be climbing for a long time before the summit sign arrives.

The headline average of 5.87% sounds civilised, but averages flatten out the story. With a maximum gradient of 15.33% recorded somewhere on the ascent, there are stretches where the road bites hard — roughly two and a half times steeper than the mean. Plan for the spikes, not the average.

How the Gradient Unfolds

The gap between the 5.87% average and the 15.33% maximum tells you this is not a metronomic climb. Over 18.4 km, a 5.87% mean produces the 1083 m of net gain, but the extra ascent beyond that — the difference between 1128 m of total ascent and 1083 m of net gain — means there are short reliefs or dips that you then have to re-climb.

Practically, expect the ramps to arrive unevenly: pitches near 15.33% will force you out of rhythm, followed by gentler sections that let your heart rate settle back toward the 5.87% cruising effort. The smart approach is to treat the steep bites as isolated efforts and refuse to chase your average on the shallow parts.

Pacing Notes

On a climb this long, pacing beats bravado. Aim to hold a steady percentage of your FTP — for most riders, sitting just under threshold for the full 18.4 km is far more sustainable than surging on every ramp. If you don't know your number, run it through the FTP estimator first so your target watts are grounded in data rather than guesswork.

Save a margin for the 15.33% pitches. Those are where riders blow up, because holding constant power on a 15.33% wall means a much lower speed and higher torque. Let the effort rise briefly there, then recover on the flatter grades back toward the 5.87% baseline.

Gearing

With 18.4 km averaging 5.87% and spikes to 15.33%, gear low and gear early. A compact chainring paired with a wide-range cassette is the sensible baseline: 34×32 will get most fit riders up the bulk of the climb, but the 15.33% ramps late in an 18.4 km effort punish anything too tall. If your legs will be deep into fatigue by the summit at 1091 m, choose 34×34 for extra insurance — the lower gear lets you spin the steep pitches rather than grind them, protecting your knees and your remaining matches.

Summary

Passo del Fo' is a long category 1 climb that rewards patience: 18.4 km, 1083 m of net gain, and steep 15.33% pitches that demand respect. Pace to your threshold, gear low, and let the summit at 1091 m come to you.

Length: 18.4 km
Average gradient: 5.87%
Max gradient: 15.33%
Start: 8 m
Summit: 1091 m
Net gain: 1083 m
Total ascent: 1128 m
Category: 1