Alto de la Pared

Overview

Alto de la Pared is a climb that reads more like a dare than a road. Over 17.1 km it averages 13.68%, a figure that belongs in a different category of suffering than the classic Grand Tour giants. You start at 1369 m and finish at 3713 m, a net gain of 2344 m, with the total ascent measured at 2331 m confirming the road barely relents once it points up. The category tells the rest of the story: HC, hors catégorie, the label reserved for climbs deemed beyond ordinary classification. This is not a climb you ride into shape on. It is one you respect before you turn a pedal.

How the Gradient Unfolds

The defining number here is the average: 13.68% sustained across the full 17.1 km. On most climbs that figure would describe a brutal isolated ramp; here it is the baseline you live at for the better part of an hour or more. With a maximum pitch of 36.09%, there are sections that go far beyond merely steep and cross into terrain where staying upright and keeping momentum become the whole task. The spread between a 13.68% mean and a 36.09% peak means the climb is not uniformly graded — expect walls that spike well above the average, forcing you out of any comfortable rhythm and demanding repeated surges just to keep the wheels turning. Add the altitude: finishing at 3713 m, the thinning air steadily erodes the power you can produce, so the final kilometres feel harder than their gradient alone suggests.

Pacing Notes

Pace this one off numbers, not feel — feel lies on a climb this long and this steep. Anchor your effort to your FTP and hold well below threshold from the base, because 2344 m of climbing leaves zero margin for an early overreach. If you don't know your current threshold, run it through the FTP estimator before you commit to a target. Remember that altitude blunts sustainable power the higher you go, so the wattage that feels controlled at 1369 m will not be repeatable near 3713 m. Treat the max ramps as short over-threshold efforts to be absorbed, then settle straight back to your climbing number.

Gearing

Gear for survival, not pride. With a 13.68% average and 36.09% pitches, a standard compact alone will leave you grinding. A 34×32 is the practical floor here, and even then the steepest ramps will have you barely spinning. If your knees or your legs prefer to keep cadence up over 17.1 km, go to a 34×34 — the extra range buys you a lighter gear precisely where the road bites hardest. On a climb this relentless, easier gearing is not weakness; it is what keeps you seated and turning instead of stalled.

Summary

Alto de la Pared is a genuine test of endurance, gearing and nerve — long, savagely steep, and finishing in thin air. Come prepared and it becomes one of the most rewarding HC efforts you can log.

Length: 17.1 km
Average gradient: 13.68%
Max gradient: 36.09%
Start: 1369 m
Summit: 3713 m
Net gain: 2344 m
Total ascent: 2331 m
Category: HC