Alto de Chilaba

Overview

Alto de Chilaba is a category 1 climb that asks for patience before it asks for power. Over 17.3 km the road lifts you from a start elevation of 1855 m to a summit at 2849 m, a net gain of 994 m at an average gradient of 5.74%. That average is the headline, but it undersells the effort: at these altitudes the thin air quietly taxes every pedal stroke, and 17.3 km is long enough that pacing errors compound rather than forgive. With a max gradient of 9.93%, Chilaba is never brutally steep, yet it rarely lets you coast. This is a climb of accumulation — a slow, relentless gathering of vertical metres.

How the Gradient Unfolds

The numbers tell a coherent story. A 5.74% average across 17.3 km, topping out at 9.93%, means the climb is steady rather than spiky. There are no wall-like ramps to shatter your rhythm, but also few genuine breathers. The difference between the 994 m net gain and the 971 m total ascent is small, which confirms there is almost no descending mixed in — the road simply climbs, and keeps climbing. Expect long sustained stretches sitting near or just above the average, punctuated by the occasional pitch drifting toward that 9.93% maximum. Because the hardest gradient is less than double the average, the smart approach is to treat the whole 17.3 km as one continuous effort rather than a series of separate attacks.

Pacing Notes

On a climb this long and this even, your FTP is the single most useful reference you have. Chilaba rewards riders who lock onto a sustainable percentage of FTP early and hold it, resisting the temptation to push on the shallower sections. Over 17.3 km, a small surge that feels free at the bottom can quietly bankrupt you well before the 2849 m summit — and altitude only sharpens that penalty. If you are unsure what number to target, run your figures through the FTP estimator and set a ceiling you can defend for the full climb. Aim to arrive at the steeper 9.93% pitches with headroom, not with your legs already emptied. Breathe deliberately; at 2849 m every watt costs more oxygen than it would at sea level.

Gearing

Chilaba's steady 5.74% average with ramps to 9.93% makes a compact chainring the obvious choice. Most riders will be comfortable on a 34×32 for the sustained sections, spinning a cadence they can hold across all 17.3 km. But given the length, the altitude, and the near-10% pitches arriving late in the effort, do not be shy about a 34×34. That extra sprocket is cheap insurance on a climb where fatigue and thin air combine — the ability to keep the pedals turning when your legs protest is worth far more than the pride of a smaller cassette. Gear for the top of the climb, not the bottom.

Summary

Alto de Chilaba is a long, honest category 1 climb: 17.3 km of near-constant ascent, an even 5.74% gradient, and a summit high enough that the altitude becomes part of the challenge. Pace it patiently, gear it generously, and let the 994 m come to you.

Length: 17.3 km
Average gradient: 5.74%
Max gradient: 9.93%
Start: 1855 m
Summit: 2849 m
Net gain: 994 m
Total ascent: 971 m
Category: 1