Puerto de las Eras

Overview

Puerto de las Eras is a long, patient Spanish climb: 18.9 km of road that carries you from a low base of 65 m up to a summit at 836 m. On paper the average gradient is a modest 4.08%, and that number tells you most of what you need to know about its character. This is not a wall-of-a-climb that forces you into the red in the opening kilometre. It is a category 2 ascent that rewards riders who can hold a rhythm for the better part of an hour, and it punishes those who spend their matches early. With 771 m of net elevation gain spread across nearly nineteen kilometres, the challenge here is one of endurance and control rather than raw explosive power.

How the Gradient Unfolds

The headline figure of 4.08% hides a more textured reality. Total ascent comes in at 795 m against a net gain of 771 m, meaning there are small dips and false flats along the way where the road briefly gives back some of the height you have won. Those 24 m of extra climbing (795 m minus 771 m) are scattered as rolling relief rather than concentrated in one spot. The steepest pitch tops out at 8.32%, roughly double the average, so expect the road to steepen noticeably in places even though it never becomes brutally vertical. The pattern is classic for a long, medium-grade pass: stretches near or below the average that let you settle, punctuated by ramps toward that 8.32% maximum that ask for a gear change and a moment of focus.

Pacing Notes

Because the climb runs 18.9 km at 4.08%, this is an effort best measured against your FTP. Aim to sit just below threshold for the bulk of the ascent and keep a little in reserve for the sharper ramps toward 8.32%. Riders who go out hard on the shallow lower slopes almost always pay for it later. If you are unsure of your numbers, run them through the FTP estimator before you plan your target power. On a climb this long, holding a steady, sustainable effort will beat surging every single time — the metronome wins here.

Gearing

At an average of 4.08% you do not need extreme gearing, but the 18.9 km length and the 8.32% max pitches make a compact setup the sensible choice. A 34×32 will handle most of the climb comfortably, letting you spin a high cadence and protect your legs over the long haul. If you are carrying fatigue, riding at altitude, or simply prefer to keep your cadence high on the steeper ramps, a 34×34 gives you that extra cushion without penalty. For a sustained category 2 effort, err toward the easier gear — you will be turning the pedals for a while, and spare range costs you nothing.

Summary

Puerto de las Eras is a rhythm climber's ascent: long, steady, and honest, with just enough steepening to keep you honest. Pace it against your threshold, gear low, and let the kilometres come to you.

Length: 18.9 km
Average gradient: 4.08%
Max gradient: 8.32%
Start: 65 m
Summit: 836 m
Net gain: 771 m
Total ascent: 795 m
Category: 2