Collada del Rei

Overview

Collada del Rei is a category-2 climb that stretches 10.1 km and rises from a start elevation of 491 m to a summit of 997 m. That gives it a net elevation gain of 506 m, with 488 m of total ascent logged along the way. The average gradient is a steady 5.01%, but the maximum ramp bites at 9.03% — so this is not a climb you can switch off on. It sits squarely in the "long enough to hurt, steep enough to respect" bracket: not hors catégorie, but a genuine test of pacing over the better part of ten kilometres.

How the Gradient Unfolds

The headline number is 5.01%, and for much of the climb the road hovers close to that figure. What makes Collada del Rei interesting is the spread between that average and the 9.03% maximum — a gap of roughly four percentage points. That tells you the climb is not perfectly uniform: expect stretches that sit comfortably below 5%, offset by pitches that nearly double it. Because the net gain (506 m) sits slightly above the total ascent figure of 488 m, the profile trends relentlessly upward with little in the way of genuine descent to break it up. Read the road ahead: when it kicks toward that 9.03% ceiling, you want to already be in the right gear rather than scrambling for one.

Pacing Notes

Over 10.1 km, the smart play is to ride the whole climb a touch under your threshold rather than surging on every ramp. Anchor your effort to your FTP: for a sustained climb of this length, holding just below FTP keeps you out of the red on the 9.03% pitches while still moving well on the flatter 5% sections. If you don't know your number, run the numbers through the FTP estimator before you go — it changes how you budget the effort across all 10.1 km. The classic mistake here is treating the early kilometres like the average and then blowing up when the gradient spikes. Bank patience early, spend it on the steep bits.

Gearing

With an average of 5.01% and ramps to 9.03% over more than ten kilometres, gearing is about protecting your cadence when the road tilts. A compact chainring paired with a wide cassette is the sensible baseline. For most riders a 34×32 will cover the bulk of the climb comfortably, giving you a bail-out gear for the steeper pitches without spinning out on the shallower sections. If you're carrying fatigue, riding at a heavier body weight, or simply prefer to spin, step up to a 34×34 — the extra range on the steepest ramps toward 9.03% is cheap insurance for tired legs late in a 506 m ascent.

Summary

Collada del Rei rewards riders who respect its length and its spikes in equal measure. Pace it just under threshold, gear it for the 9.03% ramps, and let the steady 5.01% average carry you to the 997 m summit.

Length: 10.1 km
Average gradient: 5.01%
Max gradient: 9.03%
Start: 491 m
Summit: 997 m
Net gain: 506 m
Total ascent: 488 m
Category: 2