Alto de La Raya

Overview

Alto de La Raya is a hors catégorie ascent that earns its rating the hard way: 15.9 km of climbing at an average gradient of 7.34%. From a start elevation of 1114 m, the road grinds all the way to a 2279 m summit, a net gain of 1165 m over its length. That is a genuine high-mountain effort, the kind of climb that rewards patience and punishes anyone who treats the lower slopes as a warm-up.

The numbers tell you most of what you need to know before you turn a pedal. A 7.34% average across nearly sixteen kilometres is relentless rather than explosive, but the 17.23% maximum gradient warns that the road does not stay polite. Total ascent comes in at 1155 m, close to the net gain, which means there is very little respite built into the profile — you climb, and then you keep climbing.

How the Gradient Unfolds

Read the profile as a long, sustained wall rather than a series of walls. With the average sitting at 7.34% and the ceiling at 17.23%, the climb is defined by the gap between those two figures. Where the road sits at or near the average, you can settle into a rhythm. Where it spikes toward that 17.23% maximum, cadence collapses and the effort briefly turns anaerobic.

Because net gain (1165 m) and total ascent (1155 m) are almost identical, there is essentially no coasting or false-flat recovery to bank on. Every kilometre contributes elevation. Plan your climb assuming the gradient rarely lets go, and treat any easing stretch as a chance to breathe, not to attack.

Pacing Notes

The smart way up La Raya is to ride the average and refuse to chase the steep pitches. Anchor your effort to your FTP: on an HC climb this long, holding a steady sub-threshold power costs far less than repeatedly surging over the 17.23% ramps and blowing up before the 2279 m summit.

If you do not have a reliable threshold number, get one before you commit to 1165 m of vertical. Use the FTP estimator to set a realistic ceiling, then subtract a margin for the altitude gain — the thinner air near the top makes the closing kilometres feel harder than the gradient alone suggests. Keep something in reserve for the steepest ramps, where you have no choice but to spend it.

Gearing

For a 15.9 km climb averaging 7.34% with pitches to 17.23%, gear low and gear early. A compact chainring with a wide-range cassette is the baseline: 34×32 is the minimum most riders should bring, and it will get you up the average grade at a survivable cadence. But for the 17.23% sections — and to protect your legs across the full 1165 m of gain — 34×34 is the safer choice. The extra sprocket buys you cadence exactly where the road tries to stall you. On a climb this sustained, spinning a lower gear almost always beats grinding a bigger one.

Summary

Alto de La Raya is a true HC test: long, steep, and unbroken from base to top. Respect the average, gear for the maximum, pace to your threshold, and the 2279 m summit is very much within reach.

Length: 15.9 km
Average gradient: 7.34%
Max gradient: 17.23%
Start: 1114 m
Summit: 2279 m
Net gain: 1165 m
Total ascent: 1155 m
Category: HC