Coll de Sant Roc de Viu

Overview

The Coll de Sant Roc de Viu is a short climb that never lets you settle. Over just 6.4 km it averages a punishing 9.57%, dragging you from a start elevation of 828 m to a 1440 m summit — a net gain of 612 m. That average alone puts it in serious company, and the category-1 rating is earned honestly: this is the second-hardest bracket below full hors catégorie, and the numbers explain why. There is no gentle valley run-in baked into these figures, no long false flat to hide behind. From the first pedal stroke you are climbing, and the gradient rarely dips into territory you'd call recovery.

How the Gradient Unfolds

The defining trait here is the gap between the 9.57% average and the 16.72% maximum. When a climb this steep on average still hides pitches more than seven points harder than the mean, it means the ramps come in violent, concentrated doses. Expect the road to lurch into the mid-teens where the terrain forces it, then fall back toward — but never far below — that near-double-digit average. With only 6.4 km to work with, there is no room for the gradient to average itself out over gentle kilometres; every steep section pulls its full weight on your legs. The 612 m of net gain across such a short distance confirms the relentless shape: this is a climb built from sustained pressure punctuated by savage kicks.

Pacing Notes

On a wall this steep, pacing is everything. The single biggest mistake is chasing the early ramps and blowing before the 16.72% pitches arrive. Aim to hold a steady effort anchored just below your threshold — your FTP is the number that matters most here, since sustained climbs like this are essentially threshold tests with gravity attached. If you don't know yours, run the numbers through the FTP estimator before you plan an attempt. Ride the shallower sections a touch harder to bank tempo, then let your effort spike briefly through the steepest ramps rather than trying to hold constant speed. With 6.4 km at 9.57%, a rider who paces evenly will pass those who sprinted the opening slopes.

Gearing

Do not underestimate what 9.57% average and 16.72% max demand from your cassette. For most riders, a compact 34-tooth chainring paired with at least a 32-tooth sprocket — a 34×32 — is the sensible floor here, and even then you'll be grinding through the steep pitches. If you have any doubt about your climbing legs or you're carrying fatigue, go to a 34×34. That extra sprocket keeps your cadence alive through the 16.72% ramps and protects your knees over the full 612 m of climbing. Spinning a slightly easier gear costs you nothing on a climb this short and saves you plenty when the road rears up.

Summary

The Coll de Sant Roc de Viu is a compact, uncompromising category-1 test: 6.4 km that never eases, averaging 9.57% with ramps to 16.72%. Pace it below threshold, gear low, and respect the wall.

Length: 6.4 km
Average gradient: 9.57%
Max gradient: 16.72%
Start: 828 m
Summit: 1440 m
Net gain: 612 m
Total ascent: 598 m
Category: 1