Col d'Ey

What to Expect on the Col d'Ey

The Col d'Ey is a Category 3 climb in France that covers 6.3 km and accumulates 421 m of total ascent from a starting elevation of 372 m. On paper, a 5.24% average gradient sounds manageable. In practice, a maximum gradient of 18.71% means the road conceals at least one section that will demand real respect — and a well-thought-out pacing strategy before you hit the lower slopes.

The net elevation gain of 329 m versus the total ascent of 421 m tells you the road isn't a clean, linear ramp. Expect some undulation — likely a short rollback or false flat somewhere on the route — before the final push to the summit at 701 m.

Gradient Profile

With an 18.71% maximum set against a 5.24% mean, the gradient variance here is significant. That spread signals steep ramps interspersed with gentler passages rather than a consistent grind from bottom to top.

• Lower slopes: The climb begins at 372 m. Early gradients likely sit closer to the average or below, giving legs a chance to settle into a rhythm.
• Mid-section: Where the road kicks — somewhere in this band you can expect the gradient to surge well above average, potentially approaching or hitting that near-19% ceiling.
• Upper slopes: The final kilometres to the 701 m summit may ease back toward the average, but arriving there with legs already stressed by the steep mid-climb sections changes how that feels.

Pacing Notes

A 5.24% average over 6.3 km is a climb you can ride at a steady threshold or sub-threshold effort for most of its length — but only if you budget for the steep ramps. Blow through those at too high a wattage and the remainder of the climb becomes a damage-limitation exercise.

Key principles for this climb:

• Identify the steep section early. If you have a head unit with gradient display, watch for the road kicking past 10% — that's your cue to back off slightly before the gradient peaks.
• On the steepest ramp (up to 18.71%), drop to your lowest gear early rather than grinding. Cadence collapse on a near-19% pitch accelerates fatigue fast.
• After the steep section passes, resist the urge to surge. The climb continues; use any easing gradient to recover before the summit.
• The undulating nature of the profile (evidenced by the difference between net and total ascent) means brief descents or flat sections exist — use them for active recovery, not coasting.

Gearing

For a climb with a sub-6% average you might be tempted to run a standard chainset, but the 18.71% maximum argues against it. A compact chainset (50/34) or a 1x setup with sufficient range at the rear is strongly recommended. On a near-19% gradient, running out of gears is a serious problem — particularly if fatigue has already set in from the mid-climb ramps.

If you're unsure whether your current gearing matches your fitness level on a climb like this, the FTP estimator can help you model sustainable power output against gradient demands.

Summary

The Col d'Ey is a Category 3 climb that earns its place in a training ride or race through gradient variance rather than sheer length. Six-point-three kilometres at 5.24% average is achievable for most trained riders, but the nearly 19% maximum gradient requires a measured approach from the bottom. Treat the average as a guide for overall effort, and treat the steep ramps as the climb's real test.