Portillo de Azkarate

Overview

The Portillo de Azkarate is a short, savage effort that packs an enormous amount of vertical into very little road. Over just 3.1 km it climbs from 525 m to 931 m, a net gain of 406 m at an average gradient of 13.11%. That figure alone tells you almost everything: this is a wall, not a rhythm climb. There is no gentle valley approach to warm the legs and no false-flat to recover on. The moment the road tilts up, it stays up, and it demands respect from the first pedal stroke. Rated Category 1 — one step below hors catégorie — it earns that ranking not through length but through relentless, sustained steepness that never lets the heart rate settle.

How the Gradient Unfolds

With a 13.11% average and a maximum of 18.92%, the defining feature of Azkarate is how little variance there is between "hard" and "brutal." On many climbs the average is diluted by flatter sections; here the average sits so high that even the easier ramps are punishing. The gap between the 13.11% mean and the 18.92% peak is under six percentage points, which means the steepest pitches are not isolated shocks but simply a harder shade of an already severe climb. Expect the gradient to hover in double digits throughout, with the worst ramps arriving as sharp kicks that force you out of the saddle. Total ascent of 379 m across 3.1 km confirms there is essentially no recovery built into the profile.

Pacing Notes

On a climb this steep, pacing is less about tactics and more about survival math. Your FTP will be the single biggest predictor of how this climb feels — at 13.11% average, even holding threshold power leaves you crawling, so most riders will spend the entire 3.1 km above their sustainable ceiling. Go out too hard on the opening ramps and the 18.92% pitches later will break you completely. If you don't know your threshold number, run the numbers through the FTP estimator before you commit. The smartest approach is to ride just below your redline early, accept a slow forward speed, and save whatever matches you have left for the steepest kicks near the top.

Gearing

Do not under-gear this climb. With a sustained 13.11% and ramps touching 18.92%, a compact 34-tooth chainring is the bare minimum up front, and even strong climbers should think carefully about the cassette. A 34×32 is the smallest ratio I'd suggest, and honestly most riders will be far happier with a 34×34 for the steepest pitches — the extra range keeps your cadence out of the grinding zone where knees and lower back suffer. If your bike accepts a wide-range cassette beyond 34, use it. Spinning a slightly easier gear here is not a weakness; it's the difference between finishing strong and detonating on the wall.

Summary

Portillo de Azkarate is a compact monster: brief in distance, merciless in gradient, and unforgiving from bottom to top. Come with low gears, a conservative early pace, and full respect for a climb that averages over 13% for its entire length.

Length: 3.1 km
Average gradient: 13.11%
Max gradient: 18.92%
Start: 525 m
Summit: 931 m
Net gain: 406 m
Total ascent: 379 m
Category: 1