Paso Internacional Los Libertadores

Overview

Paso Internacional Los Libertadores is a hors catégorie (HC) climb — the hardest tier on the road-cycling scale, sitting above categories 1, 2, 3 and 4. It runs 22.5 km with an average gradient of 6.43%, lifting you from a start elevation of 1737 m to a summit of 3182 m. That's 1445 m of net elevation gain over the ascent, with 1417 m of measured total ascent, meaning the road climbs almost without pause from bottom to top. The steepest pitch bites at 14.6%. This is a big-mountain effort: long enough to demand patience, steep enough in places to demand respect, and finishing high enough that the thin air alone will shave watts off your legs.

How the Gradient Unfolds

The headline number is 6.43%, but averages hide the story. Over 22.5 km, an HC climb rarely delivers a steady grind — the 14.6% maximum tells you there are ramps far harder than the mean. Expect the road to breathe: shallower drags where you can settle into rhythm, punctuated by sharp kickers that spike well into double digits. With 1417 m of total ascent inside 1445 m of net gain, there is almost no descending or flat relief to recover on; nearly every metre gained stays gained. The final third also sits above 3000 m on the way to the 3182 m summit, where altitude compounds the gradient and makes the last steep sections feel steeper than the numbers suggest.

Pacing Notes

Treat this as a long, high-altitude tempo effort. On a climb of 22.5 km you cannot chase the 14.6% ramps — hit them too hard early and the back half at altitude will punish you. Anchor your effort to your FTP and hold a sustainable percentage of it for the bulk of the climb, spending matches only on the sharpest pitches. Because you finish above 3000 m, budget for reduced power at the top and start conservatively; the thin air near the 3182 m summit turns a comfortable pace into a struggle. If you don't know your threshold, run the numbers through the FTP estimator before you plan target watts. Aim to cross the line still riding, not surviving.

Gearing

At 6.43% average with 14.6% ramps and 22.5 km of near-continuous climbing to 3182 m, gear low and gear generously. A compact 34-tooth inner chainring is the sensible front. For the cassette, a 34×32 gives most riders enough range to spin the sustained sections, but on an HC ascent this long — especially with the steepest pitches arriving when your legs are already deep and the air is thin — a 34×34 is the safer, smarter choice. The extra ratio lets you keep cadence up on the 14.6% ramps instead of grinding, which preserves your legs for the high-altitude finish. When in doubt on a climb this size, take the easier gear.

Summary

Paso Internacional Los Libertadores is a true HC test: long, high, and unrelenting from the 1737 m start to the 3182 m summit. Pace it to your threshold, gear for the ramps, and respect the altitude.

Length: 22.5 km
Average gradient: 6.43%
Max gradient: 14.6%
Start: 1737 m
Summit: 3182 m
Net gain: 1445 m
Total ascent: 1417 m
Category: HC