Col de Mollo

Overview

Col de Mollo is a short, low-altitude climb in France, rated Category 4. It runs 5 km from a start elevation of 11 m to a summit at 235 m, for a net elevation gain of 224 m. On paper that is a modest afternoon effort, and the classification confirms it: this is not an alpine giant but a compact test that rewards riders who read the terrain rather than the summary line.

The number that matters most here is the gap between the net gain and the total ascent. You climb 224 m net, but the road actually forces 422 m of ascent across its length — meaning roughly 198 m of that is spent re-climbing ground you gave back on descents and dips. This is an undulating profile, not a steady drag. Expect the effort to come in bursts, with recoveries between them, and plan for the fact that the elevation gain understates the work your legs will do.

How the Gradient Unfolds

The 4.46% average is close to meaningless on a road like this. An average that low sitting alongside a 24.17% maximum tells you the climb is built from contrasts: near-flat or descending stretches that pull the mean down, punctuated by sharp ramps that spike it back up. You will not settle into one rhythm.

• Flatter and false-flat sections where the road eases or briefly tips downhill, offering genuine recovery
• Repeated short climbs stacked through the middle, each one re-earning elevation lost in the dips
• A single savage ramp hitting 24.17% — this is where the climb is won or lost, and it demands a gear in reserve

Pacing Notes

On a steady climb you would ride at even effort and let speed vary. Col de Mollo's undulation changes the calculus. Chasing even speed here punishes you: you would over-exert on the 24.17% wall and coast the flats, wasting matches. Instead, anchor your effort to a sustainable power output on the sustained pitches, then accept that you will briefly go over it on the steepest ramp — there is no way around a 24% grade except to push through it.

Use the flatter and descending sections to recover, not to attack. If you do not know your ceiling, run the FTP estimator before you ride so you know exactly how far above threshold that steep ramp will take you and how long you can hold it.

Gearing

A 24.17% maximum gradient dictates your setup. This is not a climb for a mid-compact and a tight cassette. Fit a compact or sub-compact chainset paired with a wide-range cassette — a 34×32 or 34×34 gives you a survivable cadence when the road stands up. Without it, you will be grinding a low cadence at high torque, exactly the recipe for blowing up on the wall. Check your chainset and cassette before you leave, not at the bottom of the ramp.

Summary

• Length: 5 km
• Average gradient: 4.46%
• Maximum gradient: 24.17%
• Net elevation gain: 224 m
• Total ascent: 422 m
• Category: 4

Col de Mollo is a Category 4 climb that punches above its numbers. The low average and short length hide 198 m of extra ascent and a 24.17% ramp. Pace to effort, gear low, and it becomes a manageable test rather than a nasty surprise.