Col de la Bucle

Overview

Col de la Bucle is a category-2 climb that stretches 13.2 km from a valley floor at 544 m to a summit at 1241 m. That works out to 697 m of net elevation gain at an average gradient of 5.26%. It is long enough to demand real pacing discipline but never so brutally steep that it snaps you outright — the steepest pitch tops out at 9.01%, and much of the road sits well below that. This is a rhythm climb, the kind you settle into for the better part of an hour and try not to overcook in the opening kilometres.

How the Gradient Unfolds

The headline number, 5.26%, is deceptively gentle for a climb of this length. Averages smooth over the texture, and the gap between the 5.26% mean and the 9.01% maximum tells you the road is not uniform. Expect stretches that sit comfortably under the average, offset by sharper ramps that drag the number upward. Note too that the total ascent recorded is 676 m against a net gain of 697 m — a sign the profile is close to relentlessly upward, with little in the way of descending relief to reset your legs. You climb, and you keep climbing. Save something for where the road tilts toward that 9.01% pitch, because that is where a comfortable tempo can quietly become a survival effort.

Pacing Notes

Over 13.2 km you want to hold a steady, sustainable effort rather than surge. A good target is to ride the bulk of the climb just under your threshold, treating FTP as your ceiling rather than your cruising speed. On a category-2 climb of this length, riding above threshold early costs you far more than it gains — the 9.01% ramps will punish anyone who arrives already in the red. If you are unsure of your number, run the FTP estimator first and build your pacing plan around it. Meter your effort so the steepest section, not the first kilometre, is where you dig deepest.

Gearing

With an average of 5.26% and a maximum of 9.01% sustained over 13.2 km, you will want a compact setup and a generous cassette. A 34×32 lowest gear is enough for most fit riders to spin the steeper ramps without grinding to a crawl. If you weigh more, carry luggage, or simply prefer to protect your knees late in a long day, a 34×34 gives you extra headroom on the 9.01% pitch and lets you keep a comfortable cadence all the way to 1241 m. Err toward the easier gear — you rarely regret it near the summit.

Summary

Col de la Bucle is a sustained category-2 effort: 13.2 km of near-constant climbing, an average that hides its share of teeth, and a maximum of 9.01% to respect. Pace it off your threshold, gear low, and let the summit come to you.

Length: 13.2 km
Average gradient: 5.26%
Max gradient: 9.01%
Start: 544 m
Summit: 1241 m
Net gain: 697 m
Total ascent: 676 m
Category: 2