Collado de Fenes

Overview

Collado de Fenes is a Category 1 climb in Spain, running 6.2 km from a start elevation of 752 m to a summit at 1311 m. On paper it is a net elevation gain of 559 m over its length, and at Category 1 it sits firmly in the range where you should plan the ascent rather than attack it blind. The average gradient of 9.04% is steep enough that there is no coasting to the top — this is a sustained, front-loaded effort from the base.

The important detail is the gap between the 559 m of net elevation gain and the 769 m of total ascent. That 210 m difference means the road does not climb cleanly: there are dips and false descents that you re-climb, so you pay for elevation you also give back. Expect the legs to register more work than the net figure implies, and expect the average gradient to understate the sharpest sections because flatter and downhill stretches drag it down.

How the Gradient Unfolds

An average of 9.04% is a blend, not a constant. With 210 m of undulation baked in, the flatter and descending portions pull the mean down, which means the climbing pitches are meaningfully steeper than 9% when you are actually on them. The steepest ramp bites at 27.89% — a wall that will drop your cadence to near-zero if your gearing is wrong.

• Short recovery or descending sections that briefly ease the load — and cost you elevation you must regain
• Repeated pitches where the road ramps back up well above the average after each dip
• A steepest ramp of 27.89% that demands your lowest gear and full commitment

Do not let the recovery sections lull you. Every metre lost is a metre re-climbed at a gradient that trends steep.

Pacing Notes

On an undulating climb like this, chasing an even speed is a trap: you will overspend on the steep ramps trying to hold a number and blow up. Pace to even effort instead, letting speed fall on the pitches and rise on the flatter sections. Anchor that effort to your sustainable power output and hold just below it on the climbing sections so the repeated ramps do not stack fatigue. If you do not know your ceiling, run the FTP estimator first and set a target you can defend for the full 6.2 km.

Gearing

The 27.89% ramp governs your gearing, not the average. Come with a compact or sub-compact chainset and a wide-range cassette — a 34×32 or 34×34 gives you a survivable cadence when the road hits its wall. On a pitch that steep you want spin, not grind, to protect your legs for the sections that follow. Check your setup before the ride: confirm the cassette and chainring, and that the rear derailleur handles the largest sprocket.

Summary

• Length: 6.2 km
• Average gradient: 9.04%
• Maximum gradient: 27.89%
• Net elevation gain: 559 m
• Total ascent: 769 m
• Category: 1

Collado de Fenes is a short but serious Category 1 climb where the 210 m of undulation and the 27.89% ramp, not the length, define the difficulty. Pace to effort, gear for the steep ramps, and treat every recovery section as elevation you will pay for twice.