Col du Dolent

Overview

The Col du Dolent is a long, honest climb that rewards patience over aggression. At 17.8 km with an average gradient of 5.37%, it sits firmly in category 1 territory — not the savage wall of an hors catégorie ascent, but a sustained effort that keeps you working from the 769 m base all the way to the 1722 m summit. The net elevation gain of 953 m tells the story of the vertical challenge, while the total ascent of 907 m confirms this is a road that mostly points upward with only minor relief along the way. Over nearly eighteen kilometres, there is nowhere to truly hide, and the climb's difficulty comes from its length and consistency rather than any single brutal ramp.

How the Gradient Unfolds

A 5.37% average across 17.8 km sounds moderate, and for long stretches it is. But averages flatten the truth: with a maximum gradient of 9.54%, there are sections nearly double the mean where the road tilts up steeply and demands a response. The 46 m difference between the net gain of 953 m and the total ascent of 907 m points to small dips or flatter interludes — brief moments where the gradient eases and the road even loses a little height before resuming its climb. Expect the profile to pulse: shallower ramps around 5% where you can settle into rhythm, punctuated by steeper kicks approaching that 9.54% ceiling that break your cadence and force a gear change. Reading the road ahead matters here.

Pacing Notes

On a climb this length, discipline beats bravado. Anchor your effort to your FTP and treat the first several kilometres as a controlled burn rather than a race — the summit at 1722 m is a long way from the 769 m start, and going too deep early on a 953 m gain will cost you badly in the final third. Aim to ride the 5.37% average sections just below threshold, then accept a temporary surge in power when the gradient rears toward 9.54%, spinning it back down as the road relents. If you're unsure what wattage your body can hold for the roughly hour-long duration this 17.8 km climb implies, run the numbers through the FTP estimator before you go, and pace to it rather than to feel.

Gearing

For a category 1 climb of 17.8 km averaging 5.37% with ramps to 9.54%, gearing should prioritise cadence preservation over the full 953 m of climbing. A compact 34-tooth inner chainring is the sensible foundation. Paired with a 34×32 low gear, most riders with solid fitness will hold a comfortable spin through the steeper pitches. If you know you fatigue on long efforts, or you're carrying weight, opt for a 34×34 — that extra sprocket buys you a lighter gear precisely when the road bites near its 9.54% maximum, keeping your legs turning rather than grinding to a stall.

Summary

The Col du Dolent is a climb of endurance and rhythm: 17.8 km of near-constant ascending, a fair 5.37% average, and just enough sting from its 9.54% ramps to keep you honest. Pace it well, gear it right, and the 1722 m summit is a satisfying reward for a steady, well-managed effort.

Length: 17.8 km
Average gradient: 5.37%
Max gradient: 9.54%
Start: 769 m
Summit: 1722 m
Net gain: 953 m
Total ascent: 907 m
Category: 1