Itaya Pass

Overview

Itaya Pass is a Category 3 climb in Japan, running 7 km from a start elevation of 440 m to a summit of 764 m. That is a net elevation gain of 324 m at an average gradient of 4.64%. On paper it reads as a moderate, sustainable effort — a climb you can settle into rather than one that forces you into the red from the base.

The number that reframes the ride is total ascent. You gain 324 m net, but you actually climb 501 m of vertical over the 7 km — a 177 m gap between net and total ascent. That surplus is undulation: sections where the road pitches up, eases, or briefly drops before climbing again. In practice it means the true climbing load is meaningfully higher than the net figure suggests, and the average gradient understates how much steady work the legs will do.

How the Gradient Unfolds

A 4.64% average is a blend, not a description. With 501 m of total ascent packed into a 7 km climb that only nets 324 m, the road clearly rises and falls rather than climbing at one steady angle. The average gets pulled down by flatter and descending sections, which means the climbing pitches sit well above 4.64% to compensate. The steepest ramp hits 18.39% — a gradient that demands respect regardless of how fresh you feel.

• Flatter or recovery sections where the road eases and the gradient drops below average
• Short kicks and repeated climbs stacked through the middle, each resetting your rhythm
• A defining steep ramp at 18.39%, well above anything the average implies

Pacing Notes

On a smooth, consistent climb you could hold even power start to finish. Itaya Pass is not that climb. With this much undulation, chasing even speed will spike your effort on every ramp and waste it on the flats. Pace to even effort instead: hold your target sustainable power output through the steep pitches, let your speed rise naturally on the shallower sections, and avoid surging to hold a number on the descents.

If you do not know your ceiling, run the FTP estimator first. Riding the steep ramps just under threshold keeps you from blowing up before the 18.39% pitch, where a controlled reserve pays off most.

Gearing

The 18.39% maximum dictates your setup, not the 4.64% average. On a ramp that steep, cadence collapses fast without enough range. Run a compact or sub-compact chainset paired with a wide-range cassette — a 34×32 or 34×34 gives you a bailout that keeps you spinning rather than grinding to a stall. Check your chainset and cassette before the ride; discovering you are over-geared on an 18% pitch is not a mid-climb problem you can fix.

Summary

• Length: 7 km
• Average gradient: 4.64%
• Maximum gradient: 18.39%
• Net elevation gain: 324 m
• Total ascent: 501 m
• Category: 3

Itaya Pass rewards riders who read past the average. Pace to even effort, gear for the 18.39% ramp, and treat the 501 m of total ascent — not the 324 m net — as the real measure of the day.