col de Lys

Overview

Col de Lys is a Category 1 climb in Switzerland, running 9.3 km from a start elevation of 764 m to a summit at 1,512 m. The net elevation gain across the ascent is 748 m, which puts its listed average gradient at 8.02%. On paper that reads as a steady, hard-but-honest effort — the kind of climb where you settle into a rhythm and hold it to the top.

The profile tells a more complicated story. The total ascent is 1,202 m, well above the 748 m net gain. That 454 m difference is climbing you do and then give back — the road rises, dips, and rises again rather than tilting up in one clean line. Every metre you descend has to be re-earned, so the effort you actually spend on Col de Lys is meaningfully higher than the net figure suggests. Plan for the harder number, not the tidy one.

How the Gradient Unfolds

The 8.02% average is a blend, not a constant. With 454 m of extra climbing folded into the ascent, long stretches sit well below average while others spike hard above it. The undulation means you will rarely hold one steady grade for long. Expect the following across the profile:

• Flatter or descending recovery sections where the road gives back elevation — use them, don't coast mentally
• Repeated short climbs that stack up, each one resetting your legs before the next
• A steepest ramp reaching 29.31%, a genuine wall that dictates your gearing choice

Pacing Notes

On a climb this lumpy, chase even effort, not even speed. Holding a fixed pace forces you to over-spend on every rise and waste the descents. Instead, meter your output by your sustainable power output: ease slightly on the flatter recovery sections and let the ramps push your speed down while your effort stays capped. If you don't know your ceiling, run the numbers through the FTP estimator before you go, so you have a wattage anchor rather than a guess. The repeated re-climbs punish riders who empty themselves early — protect a reserve for the back half.

Gearing

The 29.31% steepest ramp governs your setup, not the average. That pitch is too steep to grind on standard gearing without wrecking your legs. Fit a compact or sub-compact chainset paired with a wide-range cassette — think 34×32 or 34×34 — so you keep a spinnable cadence when the road stands up. Check your chainset and cassette before the ride; discovering you're under-geared halfway up a near-30% wall is not a problem you can fix on the road.

Summary

• Length: 9.3 km
• Average gradient: 8.02%
• Maximum gradient: 29.31%
• Net elevation gain: 748 m
• Total ascent: 1,202 m
• Category: 1

Col de Lys is a Category 1 climb that hits harder than its net gain implies. Respect the undulation, pace by effort, gear for the steepest ramp, and the mountain becomes a challenge you can ride smart rather than survive.