Alto de Cueva Mayor

Overview

Alto de Cueva Mayor is a Category 1 climb that never lets you settle. Over 9.2 km it averages 9.22%, and it starts high — the foot already sits at 1124 m of elevation, and the road tops out at 1972 m. That is a net gain of 848 m, most of it earned at a gradient that would qualify as steep on any climb and is punishing sustained over this length. With a maximum pitch of 18.18%, this is a climb where the average tells only part of the story: the hardest ramps are more than twice as cruel as the number on the sign suggests.

How the Gradient Unfolds

The defining feature here is consistency at a brutal level. A 9.22% average across 9.2 km means there are very few places to recover — the road simply keeps tilting up. The gap between the 9.22% average and the 18.18% maximum tells you where the danger lies: pitches roughly double the average will spike your effort without warning, and because the climb offers little respite, you cannot bank rest before them. Expect the steepest kicks to force you out of rhythm, then the road to fall back toward that grinding high-single-digit baseline rather than easing off. Starting at 1124 m and finishing at 1972 m, you also gain altitude as you go, so the air thins slightly toward the top just as fatigue accumulates.

Pacing Notes

On a climb this long and steep, pacing discipline decides your day. Your FTP is the reference point: at 9.22% average over 9.2 km, most riders will spend well north of half an hour climbing, so riding near or above threshold from the base is a mistake you will pay for on the 18.18% ramps. Aim to hold a steady, sustainable effort and keep a small reserve for the steepest pitches, where power naturally surges. If you are unsure of your threshold, run the numbers through the FTP estimator before you plan your target — knowing your ceiling turns those 18.18% walls from a crisis into a manageable, brief spike.

Gearing

Do not under-gear this one. With a 9.22% average and ramps to 18.18%, a compact 34-tooth chainring paired with a wide-range cassette is the sensible baseline. A 34×32 will get most fit riders up, but on the steepest sections it leaves little margin, forcing you to grind at low cadence right when the gradient bites hardest. If you have any doubt about your climbing legs — or you want to ride the 848 m of gain at a spinnable cadence rather than a muscular slog — fit a 34×34. The extra range costs you almost nothing on the average slopes and buys real relief on the 18.18% pitches near the summit.

Summary

Alto de Cueva Mayor is a Category 1 test of sustained climbing: long, steep, and unforgiving, with a summit at genuine altitude. Gear low, pace with your threshold in mind, and respect the ramps.

Length: 9.2 km
Average gradient: 9.22%
Max gradient: 18.18%
Start: 1124 m
Summit: 1972 m
Net gain: 848 m
Total ascent: 800 m
Category: 1