Passo del Casello

Overview

Passo del Casello is a long haul rather than a wall. Over 22.4 km the road lifts you from a valley floor at 80 m to a summit of 1057 m — a net gain of 977 m at an average gradient of just 4.36%. On paper that average reads gentle, and for long stretches it is. But the climb hides a 14.75% maximum pitch, and the sheer duration is what earns it category 1 status. This is a climb you settle into, not one you attack.

How the Gradient Unfolds

The headline number to respect here is the gap between average and maximum. A 4.36% mean spread across 22.4 km tells you the climb is uneven: shallow ramps and false flats must be balanced by steeper kicks to reach that 14.75% peak. Expect long, rhythmic sections where you can hold tempo, punctuated by short, sharp pitches that break your cadence.

The total ascent of 1042 m slightly exceeds the net gain of 977 m — that 65 m difference means the road undulates rather than climbing in a single clean line. Small descents or flats give the legs a brief reprieve, but they also mean you re-accelerate repeatedly, and each surge costs energy you'll want on the upper slopes.

Pacing Notes

The trap on a climb like this is going out too hard on the friendly early gradient. With 22.4 km ahead, ride the first two-thirds well within yourself. A sensible ceiling is to sit at or just below your FTP — treat that threshold as a wall you touch only on the steepest ramps toward the 14.75% max, not a level you hold for twenty minutes.

If you don't know your threshold number, estimate it first with the FTP estimator, then set a target power you can sustain for the better part of an hour. On the steep pitches, let cadence drop and power spike briefly rather than trying to hold a fixed wattage — short surges are cheaper than blowing your pacing budget early. The undulations reward a rider who stays smooth and refuses to chase every gradient change.

Gearing

The average may be moderate, but 22.4 km of climbing with pitches to 14.75% means you want range and a bailout. A compact 34-tooth inner chainring is the sensible starting point. Pair it with a wide cassette: a 34×32 gives most trained riders enough to spin the steep ramps without grinding, while a 34×34 buys extra insurance for tired legs deep into the climb or for riders carrying less climbing fitness. Given the length here, err toward the easier gear — the 34×34 lets you protect cadence over 977 m of ascent, and there's no prize for suffering on gearing that's too tall.

Summary

Passo del Casello rewards patience: a long, undulating category 1 climb where the modest 4.36% average masks both its 14.75% pitches and the pure endurance demand of covering 22.4 km uphill. Pace conservatively, gear generously, and let the summit come to you.

Length: 22.4 km
Average gradient: 4.36%
Max gradient: 14.75%
Start: 80 m
Summit: 1057 m
Net gain: 977 m
Total ascent: 1042 m
Category: 1