Alto de Los Idolos

Overview

Alto de Los Idolos is a Category 1 climb that packs serious punishment into a compact 7.1 km. The average gradient of 9.12% is brutal on its own, but the headline figure is the 24.04% maximum pitch — a wall steep enough to force even strong climbers out of the saddle. You start at 1181 m and grind up to a 1827 m summit, a net gain of 646 m over a total ascent of 632 m. At just Category 1 rather than hors catégorie, its length keeps it out of the very hardest tier, but make no mistake: a sub-8 km climb that averages north of 9% is the kind of effort that rewrites your notion of a "short" ride.

How the Gradient Unfolds

The shape here is defined by the gap between the numbers. A 9.12% average across 7.1 km means the climb almost never lets up — there is no long false flat to recover on, and precious little kindness anywhere. What makes it dangerous is the 24.04% max, roughly 15% steeper than the average. That spread tells you the road is not uniform: expect stretches that hover around the mean, punctuated by savage ramps that spike toward that 24% ceiling. With a net gain of 646 m against 632 m of total ascent, the profile is essentially relentless up, with only the faintest dips. Every metre you climb, you keep.

Pacing Notes

Discipline wins here. The single worst mistake is attacking the early slopes and blowing your budget before the steepest ramps arrive. Anchor your effort to your FTP: on a climb this steep, you'll drift above threshold on the 24.04% pitches whether you like it or not, so keep your baseline effort just under FTP on the 9% sections to leave headroom. If you don't know your threshold, run your recent numbers through the FTP estimator before you plan. Meter yourself across the full 7.1 km — with 646 m of vertical to gain, patience in the first half is what keeps the summit reachable.

Gearing

Do not under-gear this one. With a 9.12% average and ramps to 24.04%, most riders will want the widest range they can fit. A compact chainring paired with a wide cassette — think 34×32 as a sensible floor — gives you a fighting chance on the sustained sections. But on the 24.04% pitches, 34×32 can still leave you mashing at a cadence that torches your legs. If your derailleur allows it, go to 34×34 for genuine insurance on the steepest walls. The extra sprocket buys you spin instead of grind, and over 7.1 km of near-constant climbing, protecting your cadence protects your ride.

Summary

Alto de Los Idolos is short, steep, and unforgiving — a Category 1 climb that behaves like something harder. Respect the 24.04% ramps, gear low, and pace to the full 7.1 km. Do that, and the 1827 m summit is yours.

Length: 7.1 km
Average gradient: 9.12%
Max gradient: 24.04%
Start: 1181 m
Summit: 1827 m
Net gain: 646 m
Total ascent: 632 m
Category: 1