Pas de Lachat

Overview

Pas de Lachat is a 12.1 km category 2 climb that lifts you from a start elevation of 458 m to a summit at 1133 m. The net elevation gain is 675 m, giving an average gradient of 5.6% across the full ascent. That number reads gently, but the climb hides a fiercer side: pitches touch a maximum of 23%, so the effort is anything but uniform. At category 2, it sits in the middle of the difficulty ladder — well short of the hors catégorie monsters, yet long and steep enough to command respect and reward good pacing over guesswork.

How the Gradient Unfolds

The headline figure of 5.6% is an average, and averages flatten the truth. Over 12.1 km, a total ascent of 635 m is spread unevenly, which tells you the road is not a constant ramp. Expect stretches that sit comfortably below the 5.6% mean, punctuated by sharper kicks that spike toward the 23% maximum. The gap between the 675 m net gain and the 635 m total ascent also hints at brief respites where the road flattens or dips slightly, letting you recover before the next rise. Read the climb in blocks: settle on the shallower sections, then brace for the steep pitches that define the hardest metres.

Pacing Notes

The smartest way to ride a 12.1 km effort like this is to anchor your pace to sustainable power rather than ego. Aim to hold a percentage of your FTP that you can carry for the full duration — for a climb of this length, that usually means riding just below threshold on the steady sections and accepting short surges above it on the 23% ramps. If you do not know your threshold, the FTP estimator will give you a working number to plan around.

Because the average is only 5.6%, it is tempting to attack early. Resist it. Bank your energy for the steep pitches, where the gradient — not your speed — dictates the cost. Keep your cadence high and your effort even, and the 675 m of climbing will feel measured rather than punishing.

Gearing

With ramps reaching 23% on a climb this long, gearing is your friend. For most riders, a compact 34-tooth chainring paired with a wide cassette is the sensible choice. A 34×32 bottom gear will get many trained cyclists over the steepest sections while keeping cadence respectable. If you weigh more, ride less often, or simply want insurance against the 23% pitches late in a 12.1 km effort, step up to a 34×34. The extra range costs you almost nothing on the shallower stretches near the 5.6% average and buys real comfort when the road bites.

Summary

Pas de Lachat is an honest category 2 climb: long enough to test your pacing, steep enough to test your gearing, and rewarding for riders who respect the numbers over the full 12.1 km. Pace to your threshold, gear for the ramps, and the summit at 1133 m is well within reach.

Length: 12.1 km
Average gradient: 5.6%
Max gradient: 23%
Start: 458 m
Summit: 1133 m
Net gain: 675 m
Total ascent: 635 m
Category: 2