Colma di Binate

Overview

Colma di Binate is an HC climb — hors catégorie, the hardest rating there is — and the numbers explain why. Over 8.4 km it averages a brutal 10.62%, lifting you from a start elevation of 227 m to a summit at 1123 m. That works out to 896 m of net elevation gain, with 880 m of total ascent packed into a road that rarely offers a moment of relief. An average above ten percent held for the better part of nine kilometres is the kind of statistic that separates a hard climb from a genuinely feared one, and Colma di Binate sits firmly in the latter camp.

How the Gradient Unfolds

The defining feature here is the near-total absence of easy ground. With a 10.62% average sustained across 8.4 km, there is no long false-flat to recover on and no shallow run-in to warm the legs. The pitch spikes to a maximum of 20.47% — roughly double the average — so the steepest ramps are savage, but even the "gentle" stretches sit in double digits. The gap between the 896 m net gain and the 880 m of total ascent tells you the road climbs almost relentlessly upward, with virtually no descending or flat to break the rhythm. Expect the effort to feel remarkably even in its difficulty: the climb simply asks for the same enormous power output, over and over, until you reach 1123 m.

Pacing Notes

On a climb this steep, pacing is survival. The single biggest mistake is chasing the early ramps and blowing your budget before halfway. Anchor your effort to your FTP and hold something close to a sustainable threshold, accepting that the 20.47% pitches will briefly push you above it — that is unavoidable, but keep those surges short and settle back down quickly afterward. If you do not know your threshold number, estimate it first with the FTP estimator so your target wattage is grounded in real data rather than optimism. At 10.62% average, your speed will be low and every second of over-pacing early costs you dearly across the full 8.4 km.

Gearing

Do not under-gear this one. With a 10.62% average and ramps hitting 20.47%, most riders will want the easiest cassette they can bolt on. A compact 34-tooth chainring paired with a 34×32 is a sensible minimum for strong climbers, but honestly, on an HC wall like this, a 34×34 is the smarter default — the extra sprocket buys you cadence and spares your knees on the 896 m of climbing. If your bike allows an even wider range, use it. The goal is to keep spinning rather than grinding to a near-standstill on the steepest pitches.

Summary

Colma di Binate is a pure HC test: relentless, steep, and unforgiving from bottom to top. Respect the average, gear low, pace with discipline, and the summit at 1123 m is yours.

Length: 8.4 km
Average gradient: 10.62%
Max gradient: 20.47%
Start: 227 m
Summit: 1123 m
Net gain: 896 m
Total ascent: 880 m
Category: HC