Alto del Infierno

Alto del Infierno cycling climb profile

Alto del Infierno is a long Category 1 ascent in CO, rising from 248 m to 1,354 m over 20.4 km. The core difficulty is not a savage average gradient, but the duration of the effort. At 5.41%, it sits in that awkward zone where it is easy to ride too hard early because the road rarely feels extreme, then pay for it once the accumulated elevation gain starts to bite.

The climb gains 1,106 m net from bottom to summit. That tells you the main story: this is a sustained uphill job rather than a short explosive test. The supplied total ascent is 1,098 m, which points to a profile dominated by upward momentum rather than meaningful downhill recovery. In practical terms, do not count on free speed or soft sections to reset the legs.

How the gradient rides

The average gradient of 5.41% suggests much of the climb should feel manageable if ridden under control. But the maximum gradient of 9.86% changes the pacing equation. A climb can average just over 5% and still punish poor gear choice when it kicks close to double digits, especially after the early freshness has gone.

Because the available profile does not include kilometer-by-kilometer gradient splits, the safest way to read Alto del Infierno is as a long steady ascent with sharper ramps embedded inside it. The road rises from a low start at 248 m to a summit at 1,354 m, so the effort gradually stacks up. The hardest sections are not only the places where the gradient touches 9.86%, but the moments after them, when you need to settle back into rhythm without having burned through too much of your sustainable power.

Pacing and gearing

The right approach is disciplined and slightly conservative. Ride the lower slopes below your hard limit, even if the 5.41% average makes it tempting to press. On a climb of 20.4 km, early surges are expensive because there is too much road left to repair the damage.

Use gearing that keeps cadence smooth when the gradient moves toward the 9.86% maximum. If you are forced to grind on the steepest pitches, your effort will spike above what the climb demands overall. That is the trap: Alto del Infierno is not defined by one wall, but by the combination of steady climbing and enough steepness to disrupt rhythm.

For pacing, anchor the effort around a sustainable climbing output rather than chasing speed. If you know your /glossary/ftp, this is the type of ascent where power discipline matters more than aggression. Stay composed through the steep ramps, recover back to rhythm quickly, and save the real lift in effort for the final push to 1,354 m.