Alto de Guanacas

Overview

Alto de Guanacas is a long, high-altitude Category 1 climb that asks for patience more than explosiveness. Over 26.2 km it lifts you from 2054 m to a summit of 3361 m, a net gain of 1307 m. The total ascent comes in slightly higher at 1386 m, meaning there are brief false-flats or dips along the way that hand back a little of the elevation you've already earned. At a 5% average gradient the climb never looks intimidating on paper, but the sheer distance — and the thin air at over 3000 m — is what turns it into a genuine test.

How the Gradient Unfolds

The defining number here is that 5% average stretched across 26.2 km. That is a climb you settle into rather than attack. If it were perfectly uniform you'd simply pick a rhythm and hold it for the better part of an hour or more. It isn't uniform, though: the max gradient of 12.6% is more than double the average, so expect the road to pitch up sharply in places while easing back elsewhere to keep the mean at 5%.

The 79 m gap between the 1386 m total ascent and the 1307 m net gain confirms the profile rolls rather than climbs in a single unbroken line. Those small descents break the tempo — pleasant for the legs, but they mean the steep sections have to work harder to make up the difference. Treat every ramp toward that 12.6% figure as a moment to stay seated, protect your effort, and let the flatter stretches restore your rhythm.

Pacing Notes

On a climb this long, discipline early pays off late. Anchor your effort to your FTP: riding the bulk of Guanacas just below threshold keeps you sustainable across the full 26.2 km without blowing up on the steeper pitches. If you don't know your threshold, run the numbers through the FTP estimator before you commit to a target.

Because the climb tops out at 3361 m, altitude will quietly trim the power you can hold — the thin air means the same perceived effort produces fewer watts than at sea level. Plan to ride a touch more conservatively than your flatland FTP suggests, especially through the second half. Save something for the ramps toward 12.6%; hitting those with empty legs is where a good ride unravels.

Gearing

With 1307 m of climbing at 5% and spikes to 12.6%, gearing generosity beats bravado. A compact 34-tooth inner chainring paired with a wide-range cassette is the sensible baseline. A 34×32 will get most fit riders up the steady sections comfortably, but on a climb this long — with altitude sapping your legs and ramps toward 12.6% — a 34×34 gives you the extra spin to protect your cadence and your knees when fatigue sets in. When in doubt on a 26.2 km effort, choose the easier gear.

Summary

Alto de Guanacas rewards the rider who respects its length. Meter your effort, gear low, and let the 5% average do the pacing for you across all 26.2 km.

Length: 26.2 km
Average gradient: 5%
Max gradient: 12.6%
Start: 2054 m
Summit: 3361 m
Net gain: 1307 m
Total ascent: 1386 m
Category: 1