Paso de Cortés

Overview

Paso de Cortés is a long, high-altitude Category 1 climb that measures 29.8 km at an average gradient of 5.11%. Over that distance it lifts you from a start elevation of 2162 m to a summit of 3684 m, delivering 1522 m of net elevation gain. The total ascent comes in at 1508 m, which tells you the road climbs almost relentlessly upward with only trivial relief along the way. This is not a wall to be conquered in a few savage minutes; it is an endurance test measured in tens of minutes, where altitude compounds every percentage point of gradient.

How the Gradient Unfolds

The headline number here is the 5.11% average, but averages flatten the story. With a maximum gradient of 12.77%, there are pitches more than twice as steep as the mean, and those ramps are what break a rhythm you have spent twenty-plus minutes building. Because the total ascent (1508 m) sits just 14 m below the net gain (1522 m), you can treat this as a near-continuous climb: there is very little descending to recover on. Expect a sustained grind punctuated by sharper kicks toward the harder double-digit sections, with the thin air above 3000 m amplifying whatever the road throws at you.

Pacing Notes

On a climb this long the discipline is everything: hold steady, resist the urge to chase the early kilometers, and let the 5.11% average dictate your effort. A useful anchor is your FTP — climbing sustainably below threshold protects you across the full 29.8 km, because there is no summit rush that can rescue a blown pacing plan on a climb this size. Riders who do not have a recent number should run the FTP estimator before attempting it, then subtract a margin for altitude: the summit at 3684 m sits high enough that power output falls noticeably compared with sea-level testing. Meter the 12.77% ramps carefully, spinning rather than mashing so you do not spike into the red on the steepest pitches.

Gearing

Given 29.8 km of continuous climbing capped by a 12.77% maximum, err generously toward easier gearing. A compact 34-tooth chainring paired with a 34×32 cassette is a sensible baseline for strong climbers, but most riders will thank themselves for a 34×34 low gear on the steep ramps late in the climb, when fatigue and altitude conspire against you. The wider 34×34 lets you keep cadence up on the 12.77% pitches without wrenching the pedals, which matters far more over 1522 m of gain than any marginal weight penalty.

Summary

Paso de Cortés rewards patience, respect for altitude, and honest pacing. Come with easy gears, a disciplined effort target, and the understanding that 29.8 km at 5.11% is an endurance climb, not a sprint.

Length: 29.8 km
Average gradient: 5.11%
Max gradient: 12.77%
Start: 2162 m
Summit: 3684 m
Net gain: 1522 m
Total ascent: 1508 m
Category: 1