Alto del Legionario

Overview

Alto del Legionario is a long, patient category 1 climb that rewards steady effort over explosive power. From a start elevation of 165 m, the road unspools for 27.3 km before topping out at 1353 m, delivering a net elevation gain of 1188 m. The average gradient sits at a deceptively mild 4.35%, but with a total ascent of 1239 m across its length, this is a climb measured in hours, not minutes. It is the sheer duration — not any single wall — that defines the challenge here.

How the Gradient Unfolds

The headline number is that 4.35% average, but averages flatten the real story. Across 27.3 km the gradient breathes: long shallow stretches let you settle into a rhythm, punctuated by steeper pitches that peak at 10.54%. That maximum is more than double the average, so the climb never lets you switch off entirely. Note too that the total ascent of 1239 m exceeds the net gain of 1188 m by 51 m — evidence of brief descents or false flats where the road gives back a little before demanding it again. Expect to grind through the gentle kilometres and brace for the ramps that punch above the average.

Pacing Notes

On a climb this long, discipline beats bravado. Anchor your effort to your FTP and resist the urge to chase the early gradient — 27.3 km is plenty of road to bury yourself on. Aim to ride the shallow sections just below threshold, banking energy for the 10.54% pitches where wattage naturally spikes. Because the climb averages 4.35%, small pacing errors compound over the full 1188 m of vertical gain. If you are unsure of your threshold, run the numbers through the FTP estimator before you set your target, then hold that ceiling steadily rather than surging.

Gearing

Duration is the enemy here, so gear for fatigue, not just for the steepest ramp. A compact 34-tooth inner chainring is the sensible foundation. Pair it with a wide-range cassette: a 34×32 gives most riders enough spin to stay seated and controlled through the 10.54% sections without cross-chaining into red. If you run less race-fit or simply value your knees over 27.3 km, step up to a 34×34 for that extra margin — the lower ratio keeps your cadence alive deep into the climb when the 4.35% average has quietly emptied your legs. Either way, prioritise a gear you can turn comfortably at hour two, not just at the base.

Summary

Alto del Legionario is an endurance climb first and foremost: 27.3 km of near-constant elevation gain that tests patience and pacing more than raw punch. Respect the length, meter your effort against threshold, and gear low enough to survive both the 10.54% ramps and the long slow burn to 1353 m.

Length: 27.3 km
Average gradient: 4.35%
Max gradient: 10.54%
Start: 165 m
Summit: 1353 m
Net gain: 1188 m
Total ascent: 1239 m
Category: 1