Collado de Somahoz

Overview

Collado de Somahoz is a short, savage category 2 climb that packs an outsized punch into its 4.3 km. The road lifts from a base at 317 m to a summit of 719 m, and while the net elevation gain is 402 m, the climb records 383 m of total ascent — a hint that almost every metre you cover is spent going up, with barely a false flat to break the rhythm.

What defines Somahoz is its average gradient of 9.41%. That is a number that would flatter a longer alpine giant; on a climb this compact, it means there is nowhere to recover. From the moment the slope tilts, you are effectively climbing at threshold or above, and the road never truly relents until you crest the top.

How the Gradient Unfolds

The headline figures tell the story of a wall rather than a staircase. With an average of 9.41% sustained across the full 4.3 km, the climb offers no gentle introduction and no soft finish — the mean is high because the gradient sits high the whole way.

The sting comes with the maximum pitch of 13.28%. That steepest ramp is nearly four points above the average, so when it arrives it will feel brutal against legs already loaded by the sustained grade. Expect the hardest sections to bite hardest through the middle and steeper pinches, where the difference between the 9.41% baseline and the 13.28% peak is enough to force a gear change or a spike well over your sustainable output.

Pacing Notes

On a climb this steep and this short, pacing is really damage limitation. There is no long enough respite to bank a recovery, so the smart approach is to hold just under your ceiling and accept that the steepest ramps will push you briefly over it.

Ride the climb relative to your FTP. At 9.41% average you will spend most of the 4.3 km at or above threshold, so aim to settle into the base sections at a controlled effort and leave a small reserve for the 13.28% pitch, where surging is unavoidable. Going too deep in the opening kilometre is the classic error here — the climb is short enough to tempt an over-eager start and long enough to punish it.

If you are not sure what number to anchor your effort to, run the FTP estimator first and set your target zones from there.

Gearing

Gear for the gradient, not the length. A climb averaging 9.41% and spiking to 13.28% will overwhelm road-race gearing for most riders, so bias toward the bottom of your cassette.

A 34×32 is the sensible minimum — it gives you a workable cadence across the sustained sections. But given how steep the maximum ramp is, a 34×34 is the safer choice for anyone not racing, keeping your legs turning through the 13.28% pinches instead of grinding to a walking-pace slog. If you tend to spin rather than mash, the extra sprockets are worth it here.

Summary

Collado de Somahoz is a genuine leg-breaker: short, unrelenting, and steep from bottom to top. Respect the average, brace for the maximum, and pick gearing that keeps you spinning.

Length: 4.3 km
Average gradient: 9.41%
Max gradient: 13.28%
Start: 317 m
Summit: 719 m
Net gain: 402 m
Total ascent: 383 m
Category: 2