Larra-Belagua

Overview

Larra-Belagua is a hors catégorie (HC) climb in Spain, rising 9.2 km through the terrain of the western Pyrenees. It carries the highest classification a climb can hold, and the numbers explain why: an average gradient of 12.79% sustained over the full distance. The road starts at 462 m and tops out at 1,639 m, for a net elevation gain of 1,177 m. That is a relentless ascent by any measure, and there is very little of the climb where you can afford to sit up.

The undulation here is worth flagging. Net elevation gain is 1,177 m, but total ascent is 1,390 m — a 213 m gap. That difference means the road does not climb in one clean line; it dips and rebounds, forcing you to re-accelerate on grades that never really relent. Every metre you give back on a descent is a metre you pay for again, and on a climb this steep the re-acceleration cost is brutal. Budget your effort for 1,390 m of climbing, not 1,177 m.

How the Gradient Unfolds

An average of 12.79% is already severe, but averages smooth over the spikes. On Larra-Belagua the 213 m of undulation tells you the profile is jagged rather than uniform, and the steepest ramps sit well above the average.

• Short recovery dips where the road gives back elevation — do not coast; keep tension.
• Repeated short climbs stacked back to back, each demanding a fresh surge.
• A steepest ramp that punches far above 12.79% — the section that decides your day.

Pacing Notes

On a uniform climb you can chase an even speed. Here, undulation makes even speed a trap: holding pace on the steep pitches means spiking your effort into the red. Pace by even effort instead. Anchor your ride to a target sustainable power output and let your speed rise and fall with the grade. On the steepest ramps, accept a slower pace rather than blowing your power ceiling. If you do not know your ceiling, run the FTP estimator before you go so your target holds up over the full 9.2 km.

Gearing

Gearing on Larra-Belagua is governed by the steepest pitches, not the average. On grades this severe, a standard setup will grind you to a stop. Run a compact or sub-compact chainset with a wide-range cassette — a 34×32 at minimum, and 34×34 if your derailleur clears it. Check your setup before the ride: confirm the cage handles the largest sprocket and that your shifting is clean under load. There is no bailout gear to reach for once you are on the wall.

Summary

• Length: 9.2 km
• Average gradient: 12.79%
• Net elevation gain: 1,177 m
• Total ascent: 1,390 m
• Category: HC

Larra-Belagua is a short climb only on paper. At 12.79% average over 9.2 km, with 1,390 m of total ascent hiding behind 1,177 m of net gain, it rewards riders who pace by effort and gear low from the start.