Alto de la Tribuna

Overview

Alto de la Tribuna is a genuine hors catégorie test, the kind of climb that reshapes a whole day on the bike. It runs for 26.6 km, lifting you from a start elevation of 1200 m to a summit at 2708 m. That is 1508 m of net gain, with 1557 m of total ascent once the small dips and false flats are counted back in. The average gradient of 5.67% sounds civil on paper, but across more than twenty-six kilometres of continuous climbing it becomes a war of attrition. Add the 17.73% maximum pitch and you have a climb that demands both patience and a top-end effort in reserve.

How the Gradient Unfolds

The headline number to respect here is the gap between the 5.67% average and the 17.73% maximum. A 12-point spread like that tells you the climb is not evenly graded — it hides steep ramps behind a moderate mean. The sheer length, 26.6 km, means the elevation is delivered gradually overall, but the near-18% maximum guarantees at least one section where the road kicks up hard enough to force you out of the saddle. Expect the profile to alternate between long, rhythmic stretches near or just below the average and sharp spikes that spike your heart rate. The difference between total ascent (1557 m) and net gain (1508 m) — a modest 49 m — confirms the road climbs almost relentlessly, with very little given back.

Pacing Notes

On a climb this long, discipline in the opening kilometres is everything. Anchor your effort to your FTP and hold a wattage you can genuinely sustain for the better part of an hour, not a heroic first-quarter surge. If you do not know your threshold, run the numbers through the FTP estimator before you go, then ride the early slopes a touch below it. Save headroom for the 17.73% maximum ramp — that is where a rider pacing off feel alone gets caught out. Climbing 1508 m of net gain rewards the even effort; the smoother your power, the more you will have left when the steepest pitch arrives.

Gearing

With 26.6 km at 5.67% average and pitches touching 17.73%, gear low and gear early. A compact 34-tooth chainring paired with a wide-range cassette is the sensible baseline. A 34×32 will get most fit riders over the moderate stretches, but on a climb with a near-18% maximum — and at altitude approaching 2708 m — the extra rescue of a 34×34 is well worth carrying. Prioritise the ability to spin a comfortable cadence over pushing a big gear; on a climb this length, protecting your legs on the ramps matters more than raw speed.

Summary

Alto de la Tribuna is a long, uneven HC monster that punishes poor pacing and rewards a low gear and a steady head. Respect the length, save something for the steep ramp, and let the average do the work.

Length: 26.6 km
Average gradient: 5.67%
Max gradient: 17.73%
Start: 1200 m
Summit: 2708 m
Net gain: 1508 m
Total ascent: 1557 m
Category: HC