Col de l'Éboulement

Overview

Col de l'Éboulement is a genuine hors catégorie (HC) climb, and its length alone earns the rating. Over 32.7 km the road rises from 639 m to a summit at 2473 m, a net gain of 1834 m. The average gradient reads a moderate-sounding 5.61%, but that number hides the reality: on a climb this long, an "easy" average is simply a wider spread between the shallow ramps and the steep ones. Total ascent comes in at 1795 m — slightly under the net gain, which tells you the profile trends relentlessly upward with only minor respites rather than any real descending. At 32.7 km, this is a climb measured in hours, not minutes, and one that rewards patience over aggression.

How the Gradient Unfolds

Read the numbers as a shape. The 5.61% average across 32.7 km is your baseline effort, but the 14.02% max gradient is nearly triple that — so expect the road to swing well above and below the mean. Because total ascent (1795 m) sits just below the net gain of 1834 m, there is almost no false-flat relief giving back elevation; you climb, then you climb some more. That means the steep sections, topping out at 14.02%, aren't isolated walls you recover from on downhills — they stack onto an already-rising road. The smart read is to treat the average as the effort you can hold all day and the 14.02% ramps as brief surges to absorb without blowing your rhythm. Thin air near the 2473 m summit only sharpens every one of those pitches.

Pacing Notes

On a 32.7 km climb, pacing is everything. Anchor your effort to your FTP and aim to sit just under it for the bulk of the ascent, holding watts steady through the 5.61% stretches so you have headroom when the road tilts toward 14.02%. Resist the temptation to chase the steep ramps — surging over threshold early will cost you far more than the seconds it saves across 1834 m of gain. If you're unsure of your threshold number, run the numbers through the FTP estimator before you start so your target watts are grounded in data, not guesswork. Remember that the final kilometres arrive above 2000 m, where altitude quietly trims your sustainable power — bank effort accordingly and finish strong rather than fading.

Gearing

Gear for the length and the 14.02% max, not the 5.61% average. On a climb of 32.7 km with 1834 m of gain, a compact chainring paired with a wide-range cassette is the sensible default. A 34×32 will get most fit riders over the steepest 14.02% pitches, but on a climb this long — where fatigue compounds hour after hour — a 34×34 gives you a lower bailout gear that keeps your cadence up and your legs intact for the thin-air summit. If your bike can take it, err toward the 34×34: you rarely regret an easier gear on an HC climb, and spinning beats grinding across 1795 m of ascent.

Summary

Col de l'Éboulement is a long-format HC test: not savagely steep on average, but unrelenting over 32.7 km to a high summit where altitude bites. Pace to your threshold, gear low, and respect the distance.

Length: 32.7 km
Average gradient: 5.61%
Max gradient: 14.02%
Start: 639 m
Summit: 2473 m
Net gain: 1834 m
Total ascent: 1795 m
Category: HC