Alto de La Virgen

Overview

Alto de La Virgen is one of those climbs that reads like a typo until you check the numbers again. It runs 22.8 km from a valley floor at 552 m to a summit at 2836 m, a net gain of 2284 m. The average gradient is a punishing 10%, and it holds that figure over nearly the full length — this is not a climb that lets you coast between efforts. Rated HC (hors catégorie, the hardest classification), it sits above even category 1 in difficulty, and the total ascent of 2262 m confirms there is almost no relief along the way.

How the Gradient Unfolds

The defining feature here is consistency, not variety. With a 10% average sustained across 22.8 km, there are no genuine flat sections to recover on and no descents to interrupt the effort — the difference between the 2284 m net gain and the 2262 m total ascent is negligible, meaning the road points relentlessly upward. Layered on top of that steady grind are pitches reaching 21% at their steepest, more than double the average. Those ramps arrive when your legs are already loaded, and they are what separate finishers from the walking wounded. Add the altitude — you finish at 2836 m, where thinner air steals watts you did not know you had — and the back half of the climb becomes as much a physiological test as a muscular one.

Pacing Notes

On a climb this long and this steep, discipline early is everything. The single biggest mistake is anchoring your effort to the 10% average and forgetting the 21% spikes will demand short surges above threshold. Ride the first two-thirds a notch below what feels sustainable. A good anchor is your FTP: on the steady 10% sections aim to sit comfortably below it, banking the headroom you will spend on the steep ramps and in the thin air near the top. If you do not know your current number, run it through the FTP estimator before you commit to a target — pacing 22.8 km off a guess is how a strong rider ends up cracked at 2836 m with kilometres still to climb.

Gearing

Do not under-gear this one. A 10% average over 22.8 km, spiking to 21%, will overwhelm a road-standard setup long before the summit. At minimum, run a compact 34-tooth chainring paired with a wide-range cassette: a 34×32 is the realistic floor, and most riders will be far happier with a 34×34, which keeps cadence alive on the 21% pitches and preserves the legs for the altitude. If your bike accepts an even larger sprocket, take it — there is no prize for grinding, and spinning a low gear is what gets you to 2836 m intact.

Summary

Alto de La Virgen is a full-day objective: 22.8 km of unbroken 10% climbing to a summit high in the thin air, with 21% ramps to keep you honest. Respect the length, gear low, and pace off real numbers.

Length: 22.8 km
Average gradient: 10%
Max gradient: 21%
Start: 552 m
Summit: 2836 m
Net gain: 2284 m
Total ascent: 2262 m
Category: HC