Coll de Merolla

Overview

The Coll de Merolla is a long, honest category 3 climb that trades brute steepness for patience. Over its full 15 km it lifts you from a valley floor at 690 m to a summit of 1193 m — a net gain of 503 m at an average gradient of just 3.35%. That number tells you most of what you need to know: this is a tempo climb, not a wall. You settle into a rhythm early and hold it, because there is far more road ahead than there is elevation to conquer.

Don't let the gentle average lull you completely, though. The gradient peaks at 10.29% somewhere along the way, and the total ascent of 527 m — 24 m more than the net gain — tells you the road isn't perfectly monotonic. There are small dips and pitches folded into the 15 km, which means your legs never get to fully switch off.

How the Gradient Unfolds

With a 3.35% average spread across 15 km, the Merolla is defined by its long, low-slung character. Much of the climb sits well under the average, which is what makes the steeper ramps feel so sharp when they arrive. The difference between the 527 m of total ascent and the 503 m of net gain confirms there are false flats and brief downhills built in — 24 m of "extra" climbing you'll do without gaining any net height.

The 10.29% maximum is the sting in the tail of an otherwise mellow profile. It's a short, punchy pitch rather than a sustained wall, but on a climb this long it can catch you out if you've spent yourself on the flatter early kilometres. Ride the gentle sections conservatively and keep that maximum in reserve.

Pacing Notes

Because the Merolla averages only 3.35%, it rewards a steady, sustainable effort rather than repeated surges. Aim to climb just below your FTP on the shallow sections, holding enough headroom to absorb the 10.29% ramp without going deep into the red. If you don't know your threshold, run the numbers through the FTP estimator before you plan your effort.

Fifteen kilometres is long enough that pacing errors compound. Start too hard on the low gradients and you'll be crawling by the summit at 1193 m. Better to ride the first two-thirds within yourself and lift the effort only when the road tilts up near the top.

Gearing

For a climb this gentle you don't need an enormous cassette, but the long duration and that 10.29% pitch make an easy bailout gear worth having. A compact chainring paired with a wide-range cassette is ideal. A 34×32 will cover the vast majority of the 15 km comfortably, letting you spin the 3.35% average without straining. If you like to climb seated at a high cadence, or you're carrying fatigue, a 34×34 gives you an extra margin for the steep ramp — well worth it on a climb where consistency matters more than power.

Summary

The Coll de Merolla is a patient rider's climb: 15 km of steady tempo with one sharp reminder near the top. Pace it evenly, gear it kindly, and let the rhythm carry you to 1193 m.

Length: 15 km
Average gradient: 3.35%
Max gradient: 10.29%
Start: 690 m
Summit: 1193 m
Net gain: 503 m
Total ascent: 527 m
Category: 3