Coll de Guirló

Overview

Coll de Guirló is a long, measured category 2 climb that rewards patience over punch. Across 17.1 km the road lifts you from a start elevation of 98 m to a summit of 803 m, a net gain of 705 m. The average gradient sits at a friendly-looking 4.12%, and the steepest pitch tops out at 6.79% — numbers that never bite hard on their own but add up relentlessly over the distance. This is a climb defined by duration rather than severity: no wall to fear, just a very long line of steady effort.

How the Gradient Unfolds

The defining feature here is the gap between the 4.12% average and the 6.79% maximum. That spread is modest, which tells you the road holds a consistent shape rather than lurching between flat drags and steep ramps. Interestingly, the net elevation gain of 705 m exceeds the total ascent figure of 635 m — a reminder that the recorded profile smooths out the small dips and levelling sections that break up the ascent. In practice you'll spend most of the 17.1 km hovering around that 4% mean, with the pitch stiffening toward 6.79% on the harder ramps before easing again. There are no double-digit surprises to blow your legs apart; the challenge is simply refusing to let the grind erode your rhythm.

Pacing Notes

On a climb this long and this even, pacing to your FTP is everything. Because the gradient rarely strays far from 4.12%, you can settle into a single sustainable power number and hold it almost the whole way up — there's little benefit to surging, and every match you burn early is one you'll miss over the back half of the 17.1 km. Aim to ride just below threshold so the 6.79% ramps don't tip you into the red. If you're unsure what wattage that means for you, run the numbers through the FTP estimator before your attempt and build your target around it. Treat the first two-thirds as a controlled tempo effort and keep something in reserve for the upper slopes.

Gearing

For a 705 m ascent at these gradients, a compact setup with a wide-range cassette is the sensible choice. A 34×32 will comfortably cover the 4.12% average and let you spin the steeper 6.79% sections without grinding. If you're carrying fatigue, prefer a higher cadence, or simply want insurance for a long day, a 34×34 buys you an extra cog and a lower floor for the same effort. Given the sustained 17.1 km, err toward the easier gear — protecting your legs early pays dividends near the 803 m summit.

Summary

Coll de Guirló is a distance climb, not a steepness climb: 17.1 km of steady 4.12% work with a manageable 6.79% ceiling. Ride it to your threshold, gear low, and let consistency carry you to the top.

Length: 17.1 km
Average gradient: 4.12%
Max gradient: 6.79%
Start: 98 m
Summit: 803 m
Net gain: 705 m
Total ascent: 635 m
Category: 2