Col de l'Allimas

Overview

Col de l'Allimas is a Category 1 climb in France, starting at 669 m elevation and topping out at 1,364 m — a net gain of 695 m across 9.6 km. The average gradient of 7.22% is demanding but manageable; the maximum gradient of 32.01% is not. That single statistic defines the character of this climb more than any other. Somewhere on these slopes there is a ramp that will stop the unprepared in their tracks.

Note that total ascent across the route amounts to 1,070 m against a net gain of 695 m, which signals meaningful undulation — the road does not simply march straight upward. Expect at least one significant dip that temporarily relieves the legs before demanding more.

How the Gradient Unfolds

With a 7.22% average over 9.6 km and a 32.01% peak, the gradient distribution is heavily uneven. A 32% ramp is roughly four times the average — this is not a statistical outlier you can simply absorb at tempo pace. It is a wall.

Practical implications:

• Lower two-thirds of the climb: The average gradient suggests this section is where you establish rhythm. Sustained double-digit gradients are likely punctuated by short flatter passages (explaining the gap between net gain and total ascent).
• The 32% spike: Without knowing its precise location, treat any sudden steepening as a candidate. Stay seated as long as possible to preserve rear-wheel traction. Standing too early on steep loose or damp tarmac risks wheel spin and power loss.
• Post-spike recovery: After a ramp that severe, the road likely eases before the final push to 1,364 m. Use any gradient relief to restore breathing and cadence rather than accelerating.

Pacing Strategy

This climb rewards conservative early pacing. A 7.22% average across nearly 10 km places this firmly in sustained FTP territory for most riders. Arriving at the 32% section with legs already deep in oxygen debt is a recipe for a full stop.

Recommended approach:

• Target 75–85% of your FTP for the opening kilometers. Use the FTP estimator if you're unsure of your current number.
• Monitor cadence: on a 7% average, dropping below 70 rpm is a warning sign that you're overcooking the effort.
• When the gradient surges toward its maximum, shift down early — before you need to, not after. On a 32% gradient, a mid-ramp gear change under load risks chain drop or a stall.
• The total ascent of 1,070 m versus 695 m net gain means your legs will accumulate more fatigue than the summit gain alone suggests. Factor this into any post-climb or multi-climb day planning.

Gearing Notes

A 32.01% maximum gradient is among the steepest gradients found on classified road climbs. Standard compact gearing (50/34 chainset with an 11-28 cassette) will leave most riders grinding or stopped at the steepest pitch. Recommended minimum for riders without a strong power-to-weight ratio:

• Chainset: 50/34 compact or 46/30 sub-compact
• Cassette: 11-32 or 11-34
• 1x riders: A 40t chainring with a 10-42 or 10-44 cassette covers the range adequately

If you're riding this as part of a longer day in the mountains, err toward the easier gearing regardless of ego. A 32% ramp mid-climb is not the place to discover you're two teeth short.

Col de l'Allimas is a Category 1 climb that earns its classification not through relentless uniform steepness but through the combination of sustained effort demand and at least one genuinely extreme gradient spike. Respect the numbers, gear appropriately, and pace the first half conservatively.