Colladeta de Tous

Overview

Colladeta de Tous is a long, patient effort rather than a short punch. Over 25.8 km the road lifts you from 926 m to a summit at 2281 m, a net gain of 1355 m at an average gradient of 5.24%. That average tells only part of the story: with a maximum pitch of 23.85%, this is a climb that hides its teeth behind a moderate headline number. Rated Category 1 — one rung below hors catégorie — it demands the kind of sustained output that rewards discipline over enthusiasm.

How the Gradient Unfolds

A 5.24% average across 25.8 km sounds forgiving, and for long stretches it is. But an average is a smoothing lie. The gap between that 5.24% mean and the 23.85% maximum is enormous, which means the easy kilometres are being paid for somewhere by ramps far steeper than the number implies. Expect the profile to breathe: shallower sections where you can settle into a rhythm, punctuated by sharp kicks that spike well into double digits. The total ascent of 1357 m sits just 2 m above the net gain of 1355 m, so there is almost no descending or false-flat give-back — nearly every metre climbed is a metre you keep. Once you are moving up, you stay moving up.

Pacing Notes

On a climb this long, pacing is everything. Anchor your effort to your FTP and resist the urge to chase the early kilometres. A steady sub-threshold power that you can hold across the full 25.8 km will beat a fast start that unravels before the summit. Save headroom for the 23.85% ramp — that pitch will tax you regardless of how well you have paced, so arrive at it with something in reserve rather than already redlined. If you do not know your threshold, run the numbers through the FTP estimator before you plan the ascent, then work backwards from a target time to a sustainable wattage.

Gearing

Do not underestimate this one because of its gentle average. The 23.85% maximum gradient is the deciding factor for gear choice, not the 5.24% mean. A compact 34-tooth chainring paired with a 34×32 will get most riders up the moderate sections comfortably, but on the steepest ramp — and after 1355 m of accumulated climbing — a 34×34 gives you the extra spin to keep cadence up and your knees intact. Given the length, err toward the easier ratio: a 34×34 costs you almost nothing on the flatter kilometres and buys real insurance for the pitches that spike toward 24%.

Summary

Colladeta de Tous is a Category 1 endurance test: long, mostly steady, with a sting in the tail that punishes anyone who ignored their gearing. Pace it to your threshold, gear for the ramp, and let the 25.8 km come to you.

Length: 25.8 km
Average gradient: 5.24%
Max gradient: 23.85%
Start: 926 m
Summit: 2281 m
Net gain: 1355 m
Total ascent: 1357 m
Category: 1