Paso de las Peñas

Paso de las Peñas cycling climb profile

Paso de las Peñas is a category 1 climb that asks for discipline from the first pedal strokes. On paper, 11.3 km at 8.37% is already a serious sustained effort. The more important detail is that the climb gains 945 m net from a start elevation of 1855 m to a summit elevation of 2800 m, while the total ascent is 984 m. That gap tells you the road is overwhelmingly uphill, but not perfectly linear. There is just enough extra climbing in the profile to suggest small variations or interruptions in the gradient, rather than a simple metronomic drag to the top.

How the gradient rides

The defining feature is the combination of a hard average gradient and an extreme maximum gradient of 28.7%. Without segment-by-segment data, the exact placement of that steepest pitch is not something to guess. But tactically, its presence changes how the whole climb should be ridden.

An 8.37% average over 11.3 km already sits in the range where torque demand stays high and recovery is limited. When a climb with that average also contains a ramp close to 28.7%, the average is not the full story. The road cannot be treated as a smooth threshold effort from bottom to summit. The steepest section will force a spike in force production, cadence will likely fall, and any rider already riding above sustainable pace will pay for it immediately.

The start at 1855 m and summit at 2800 m also mean the climb finishes far above where it begins. That matters because the final part comes after a long vertical gain, not after a short punch. The difficulty is cumulative: each steepening costs more because it arrives on top of sustained climbing load.

Pacing and gearing notes

Ride Paso de las Peñas as a controlled climbing effort, not as a test of who can handle the first hard ramp. The smartest approach is to keep the opening effort below your ceiling, settle into a pace you can hold, and leave margin for the maximum-gradient sections.

Practical setup matters here. A low climbing gear is not optional if you want to preserve cadence when the road kicks up toward its steepest pitch. If your gearing only feels comfortable on an 8% slope, it may become a limiter on the hardest ramp, where the issue is no longer fitness alone but whether you can keep turning the pedals without burning through your legs.

For pacing, use effort rather than speed. On gradients this variable, speed will fluctuate too much to be useful. If you ride with power, anchor the climb around sustainable output relative to /glossary/ftp, but accept short rises on the steepest parts rather than trying to force a flat power file. The priority is avoiding an early anaerobic cost that turns the upper section into survival.

Bottom line

Paso de las Peñas is hard because it combines real length, a strong average gradient, major vertical gain, and a severe maximum pitch. The rider who respects the whole 11.3 km will climb it better than the rider who reacts to every change in gradient.