Bocca Dromaé

Overview

Bocca Dromaé is a hors catégorie climb that gives you almost nowhere to hide. Over 15.2 km the road drags you from a valley floor at 75 m up to a summit of 1685 m, a net gain of 1610 m. The average gradient reads 10.61%, and that number is not softened by long flat stretches or false-flat approaches — it is a sustained, honest double-digit wall. Total ascent comes in at 1590 m, confirming that this is a climb that goes up and keeps going up, with barely a metre given back along the way.

For context, an HC climb is the hardest classification there is, sitting above category 1, 2, 3 and 4. Bocca Dromaé earns that label on length and gradient alone.

How the Gradient Unfolds

The defining feature here is consistency at a savage level. A 10.61% average across 15.2 km means the climb rarely lets you settle into a comfortable rhythm. Even the easier sections are steep by any normal standard, and the road repeatedly throws sharper pitches at you, peaking at a leg-breaking 28.31% maximum.

Because the net gain (1610 m) and total ascent (1590 m) are so close, you can assume almost no descending or flat recovery. Every kilometre buys roughly a hundred metres of elevation. Treat the max-gradient ramps as the crux moments: they arrive without much warning and can spike your effort well past sustainable levels if you are not already riding within yourself.

Pacing Notes

On a climb this relentless, discipline beats bravado. The single most useful reference is your FTP: on a 10.61% average for the better part of an hour or more, you want to hold an effort you can genuinely sustain, not a heroic surge that blows apart on the first 28.31% ramp.

If you are unsure of your current number, run it through the FTP estimator before you commit to a target. A good rule for Bocca Dromaé is to sit slightly below threshold on the steady sections so you have headroom for the steep ramps, where your power will naturally spike as gradient forces cadence down. Ride the first third conservatively — with 1610 m of climbing ahead, the summit is a long way off, and going into the red early on a 10.61% grade is very hard to recover from.

Gearing

Gear for the steep pitches, not the average. On a climb touching 28.31%, most riders will want the easiest ratio they can bolt on. A compact 34-tooth chainring paired with a 34×32 cassette is a sensible minimum, but on a wall this long and this steep, going to 34×34 buys you meaningful breathing room and lets you keep a spinning cadence instead of grinding to a near track-stand on the ramps. If your bike accepts a wider-range cassette, take it — protecting your knees and your composure over 15.2 km at 10.61% is worth more than a couple of grams.

Summary

Bocca Dromaé is a pure test of sustained climbing: long, uniformly steep, and topped by ramps that punish any overreach. Pace it by feel and power, gear it generously, and respect the fact that 1610 m of vertical does not care how strong you felt at the bottom.

Length: 15.2 km
Average gradient: 10.61%
Max gradient: 28.31%
Start: 75 m
Summit: 1685 m
Net gain: 1610 m
Total ascent: 1590 m
Category: HC