Colle del Ranghetto

Overview

Colle del Ranghetto is a long, serious category 1 ascent that asks for patience as much as power. Over 16.6 km it lifts you from a valley floor at 218 m to a summit of 1283 m — a net gain of 1065 m at an average gradient of 6.42%. That average alone marks it as a sustained effort, but the number that changes how you ride it is the max gradient of 20.56%: this is not a metronomic climb you can settle into and forget. The total ascent of 1053 m confirms the road climbs almost the entire way, with only slight relief along the route.

How the Gradient Unfolds

The headline figure is deceptive. A 6.42% average across 16.6 km sounds like a rhythm climb, and for long stretches it is. But a max gradient of 20.56% means the ramps here roughly triple the average, so the pain is unevenly distributed. Expect the road to swing between forgiving sections well below 6.42% and short, savage pitches that force you out of the saddle. The gap between the 218 m start and the 1283 m summit is 1065 m, yet the measured total ascent of 1053 m tells you almost none of that gain is given back — there are no meaningful descents to recover on. Plan for the climb to feel relentless, punctuated by walls rather than broken by rest.

Pacing Notes

On a climb this long, discipline beats bravado. Anchor your effort to your FTP and hold something in reserve for the 20.56% ramps, where power spikes are unavoidable and easy to overcook. A good rule: ride the sustained 6.42% sections a touch under threshold so the steep pitches don't blow you apart. Because the climb runs 16.6 km with 1065 m of vertical, small pacing errors early compound badly near the 1283 m summit. If you're unsure where your threshold sits, run the numbers through the FTP estimator before you commit to a target, then translate that into a wattage ceiling you refuse to cross on the lower slopes.

Gearing

Gearing is where this climb rewards preparation. For most riders a compact 34-tooth chainring is the sensible front end, and the cassette is the real decision. A 34×32 will get many strong riders up the 6.42% average comfortably, but the 20.56% ramps are a different problem — grinding those at low cadence on a 32 punishes your knees and drains your legs for the kilometres still to come. If you have any doubt about your climbing legs over 16.6 km and 1065 m of gain, fit a 34×34. The extra range keeps your cadence alive on the steepest walls and preserves matches for the summit push.

Summary

Colle del Ranghetto is a full-value category 1 climb: long enough to test your endurance over 16.6 km, steep enough in places at 20.56% to test your gearing, and unrelenting enough — 1053 m of total ascent against 1065 m net — to reward honest pacing over ego. Come with a low gear and a plan.

Length: 16.6 km
Average gradient: 6.42%
Max gradient: 20.56%
Start: 218 m
Summit: 1283 m
Net gain: 1065 m
Total ascent: 1053 m
Category: 1