Collado Alto

Overview

Collado Alto is a 9.8 km category 2 climb that starts at 904 m and tops out at 1484 m, a net gain of 580 m over a road that averages 5.93%. On paper the average reads like a steady tempo effort, but the total ascent of 546 m tells you the road never truly flattens — almost every metre of forward progress is metre of vertical work. With a maximum gradient of 17.65%, this is a climb defined by its steep punctuation marks rather than by any single relentless wall, and pacing it well means respecting the numbers rather than the average.

How the Gradient Unfolds

The headline figure is that 5.93% average, but averages hide the story. A climb that gains 580 m over 9.8 km while spiking to 17.65% is not a uniform ramp — it is a mix of sustained tempo sections stitched together by sharp kicks that briefly triple the average gradient. Those steep pitches are where the climb is won or lost. Expect stretches near the mean where you can find a rhythm, then abrupt ramps that force you out of the saddle or deep into your gearing. Because the total ascent (546 m) sits close to the net gain (580 m), there is very little descending or false-flat recovery hidden in the profile: what goes up mostly stays up.

Pacing Notes

Ride the average, survive the maxes. Target an effort you can hold for the full 9.8 km rather than one that feels comfortable on the opening slopes. A useful anchor is your FTP: on a climb of this length, most riders can sustain something in the region of their threshold, but the 17.65% ramps will spike your power well above it, so leave headroom. Don't chase those spikes — let your speed drop and your cadence fall on the steepest metres, then settle back to tempo once the road eases toward the 5.93% mean. If you're unsure where your threshold sits, run the numbers through the FTP estimator before you commit to a pacing plan. Banking too much effort in the first few kilometres, then bleeding time across the back half, is the classic way to lose minutes here.

Gearing

With ramps hitting 17.65%, gearing is not a place to be macho. A compact 34-tooth chainring is the sensible starting point. Pair it with at least a 34×32 for the steep sections, which gives you a low enough ratio to keep the pedals turning through the sharp kicks without grinding to a halt. If you climb at a naturally lower cadence, weigh less power-to-weight in the steep bits, or simply want insurance for the 17.65% ramps, step up to a 34×34 — that extra sprocket buys real relief when the road stands up. Given the 580 m of gain packed into under ten kilometres, err toward the easier option.

Summary

Collado Alto rewards discipline: pace to the 5.93% average, gear for the 17.65% maximum, and let the 580 m of climbing come to you across all 9.8 km. Respect the steep pitches and this category 2 ascent becomes a satisfying, rhythmic effort rather than a survival exercise.

Length: 9.8 km
Average gradient: 5.93%
Max gradient: 17.65%
Start: 904 m
Summit: 1484 m
Net gain: 580 m
Total ascent: 546 m
Category: 2