Coll de Grua

Overview

Coll de Grua is a long, patient category-3 climb that rewards rhythm over raw power. Over its full 18.6 km it averages 3.28%, lifting you from a start elevation of 109 m to a summit of 718 m. That works out to 609 m of net elevation gain, with 579 m of total ascent recorded along the way — a hint that the road is not relentlessly upward but rolls in places, giving back a little before it climbs again.

At 3.28% average, this is not a wall. It is a tempo climb: the kind of ascent where you settle into a gear, hold a steady cadence, and let the kilometres accumulate. The category-3 rating (one step above the gentlest category 4, and well short of the brutal hors catégorie) reflects exactly that — real distance, moderate slope, and a manageable ceiling.

How the Gradient Unfolds

The headline number to respect is the max gradient of 9.4%. That figure sits far above the 3.28% average, which tells you the climb is uneven rather than uniform. Long stretches will feel easy — shallower than the average — precisely so that a handful of steeper pitches can spike toward that 9.4% and still leave the overall figure at 3.28%.

The gap between 609 m of net gain and 579 m of total ascent is small but meaningful: it confirms brief downhill or flat sections break up the climbing. Expect to be rolling through kilometres that barely register on the legs, then meeting a ramp that demands you shift down and stand. Read the road ahead and treat the steep bits as short efforts rather than the new normal.

Pacing Notes

On a climb this long, discipline early pays off late. The single biggest mistake is burning matches on the first ramp toward 9.4% and paying for it across the remaining kilometres. Anchor your effort to your sustainable power. If you know your FTP, aim to sit just under it on the shallow sections and allow short surges over it on the steep pitches, letting the easier gradient afterward flush your legs.

If you are not sure of your threshold, use the FTP estimator before you ride so your pacing targets are grounded in real numbers rather than feel. With 18.6 km to cover, a watt saved in the first third is a watt you will want badly near the 718 m summit.

Gearing

Because the average is a modest 3.28%, most riders do not need extreme gearing here — but the 9.4% pitches mean you still want a bailout. A compact 34-tooth chainring paired with a wide cassette handles this profile comfortably. A 34×32 is enough for most riders to spin the steepest ramps without grinding, keeping cadence high across the full 18.6 km.

If you tire late, favour lower climbing legs, or simply want insurance for the 9.4% sections at the end of a long day, step up to a 34×34. The extra sprocket costs nothing on the shallow stretches and buys real comfort when the road kicks up 609 m above where you started.

Summary

Coll de Grua is a distance climb, not a steep one: a steady category-3 effort where patience and pacing beat aggression. Settle in, respect the 9.4% ramps, and let the 18.6 km come to you.

Length: 18.6 km
Average gradient: 3.28%
Max gradient: 9.4%
Start: 109 m
Summit: 718 m
Net gain: 609 m
Total ascent: 579 m
Category: 3