Jukkoku Pass

Overview

Jukkoku Pass is a Category 1 climb in Japan that runs 8.5 km from the coast to a summit at 594 m. It starts at sea level, at 0 m, and delivers a net elevation gain of 594 m over that distance. On paper it reads as a steady, mid-length climb with an average gradient just under 7 percent.

The paper number understates it. While the net gain is 594 m, the total ascent is 896 m, meaning you actually climb 302 m more than the start-to-summit difference implies. That gap is undulation: the road repeatedly gives back height before clawing it back. Every metre of descent mid-climb is a metre you pay for twice, so plan for the effort of a longer, harder day than the net figure suggests.

How the Gradient Unfolds

The 6.97 percent average is a blend, not a constant. With 302 m of extra climbing baked in, the profile rolls rather than ramps steadily, and the steep pitches bite hardest where you least want them. The maximum gradient reaches into the low twenties, so there are ramps that will force you out of the saddle regardless of pacing plans.

• Flatter and downhill sections that let the average drop and offer brief recovery
• Repeated short climbs stacked back to back, each undoing a piece of your recovery
• A steepest ramp in the low-twenties percent range that demands your lowest gear

Pacing Notes

On a smooth climb you can hold even watts and let speed drift. Here, the undulation makes pure even-effort pacing awkward: the descents mean you either soft-pedal and lose momentum or overcook the following ramp. Aim for even effort on the sustained pitches, but allow yourself to push slightly above your sustainable power output on the short, steep repeats, then recover on the give-back sections. Even-speed pacing is a trap here, it forces spikes on every ramp. Know your ceiling before you start; run the FTP estimator so you have a real number to pace against rather than guessing on the road.

Gearing

The steepest pitches reach into the low-twenties percent, and that governs your setup, not the average. Fit a compact or sub-compact chainset and pair it with a wide-range cassette, something like a 34x32 or 34x34, so you keep a spinnable cadence when the gradient spikes. The repeated ramps punish a cadence that collapses. Check your chainset and cassette before the ride, not at the base of the climb.

Summary

• Length: 8.5 km
• Average gradient: 6.97%
• Net elevation gain: 594 m
• Total ascent: 896 m
• Category: 1

Jukkoku Pass is a Category 1 climb that hides its difficulty in the average. The 302 m gap between net gain and total ascent is the real story: pace for the rolling profile, gear for the steep ramps, and treat the 6.97 percent number as a starting point, not the whole picture.