Alto del Zipa

Overview

Alto del Zipa is a genuine hors catégorie (HC) climb — the hardest classification on the scale, sitting above categories 1, 2, 3 and 4. Over 18.3 km it averages 7.65%, dragging you from a start elevation of 1792 m to a summit at 3195 m. That is a net elevation gain of 1403 m, achieved across a road whose total ascent is 1360 m. The numbers alone tell the story: this is a long, high, relentlessly steep ascent that rewards patience and punishes anyone who starts too hot.

How the Gradient Unfolds

The defining feature of Alto del Zipa is its sustained pitch. A 7.65% average held over 18.3 km leaves almost nowhere to recover — there is little in the way of false flat to hide behind. The maximum gradient touches 10.99%, so while the climb never sends you into truly wall-like territory, the steepest ramps sit close to 11% and arrive on top of legs already loaded by kilometres of steady effort. Because the net gain (1403 m) slightly exceeds the total ascent (1360 m), the road climbs almost continuously, with minimal give-back descending. Treat every stretch as work: the difference between the 7.65% average and the 10.99% max is where the climb bites hardest.

Pacing Notes

At 18.3 km, this is an effort measured in tens of minutes, not seconds, so pace it against your FTP rather than raw feel. A sustainable target for a climb of this length is a shade below threshold — pushing over FTP early on a 7.65% average will cost you dearly when the 10.99% ramps appear. If you are not sure where your threshold sits, run the numbers through the FTP estimator before you commit to a plan. Remember that the summit stands at 3195 m: thinner air at altitude blunts your usable power, so bank a margin and let the climb come to you. Start conservatively, hold a steady output through the middle, and keep something for the steepest pitches near the top.

Gearing

For an HC climb of 18.3 km averaging 7.65% with ramps to 10.99%, gear low and gear early. A compact 34-tooth inner chainring is the sensible foundation. Pair it with at least a 34×32 for the sustained gradient, and if you want insurance against the 10.99% sections at altitude — or if you simply prefer to spin — a 34×34 gives you the extra range to keep your cadence up rather than grinding. When a climb gains 1403 m in one continuous effort, a bail-out gear is not indulgence, it is smart pacing hardware.

Summary

Alto del Zipa is a top-tier HC test: long, high and unremittingly steep. With a 7.65% average sustained over 18.3 km and a summit at 3195 m, it demands disciplined pacing, low gearing and respect for the altitude. Get those three right and 1403 m of climbing becomes a rhythm rather than a fight.

Length: 18.3 km
Average gradient: 7.65%
Max gradient: 10.99%
Start: 1792 m
Summit: 3195 m
Net gain: 1403 m
Total ascent: 1360 m
Category: HC