Collado de Arichulegui

Overview

Collado de Arichulegui is a Category 3 climb in Spain (ES), running 12.8 km from a low start at 24 m to a summit of 481 m. On paper it is a modest ascent: the net elevation gain is 457 m, and the 3.56% average gradient reads as an easy day. Those headline numbers frame it as a steady, rolling road climb rather than a wall.

The average, however, hides the real work. Against 457 m of net gain, the profile racks up 810 m of total ascent — meaning roughly 353 m of climbing is repaid by descending along the way. That undulation matters: you pay for every metre you lose and have to regain, so the effort is higher than the net figure suggests. Treat this as a punchy, broken climb, not a smooth drag.

How the Gradient Unfolds

A 3.56% average is an accounting artifact here. Descents and flat sections drag the mean down, which means the true climbing pitches are meaningfully steeper than 3.56%. Expect the road to hand back elevation, then claw it straight back on short ramps.

• Flatter and descending recovery sections that lower the average and give you brief respite.
• Repeated short climbs stacked back-to-back, driving total ascent well above net gain.
• The steepest ramp is the crux — a sharp pitch that rewards a low gear and patience.

Pacing Notes

On an undulating climb like this, even-effort beats even-speed. Chasing a constant speed means burning matches on every short ramp and coasting on the descents — a spiky, wasteful profile. Instead, hold a steady sustainable power output and let your speed swing: faster on the flatter and downhill sections, slower on the ramps.

Know your ceiling before you start. Run the FTP estimator, then sit just under that number on the climbs and soft-pedal the descents to recover. The 353 m of give-back elevation is a gift — use it to reset your legs rather than pressing on.

Gearing

The steepest ramp governs your gearing, and it is steeper than the average implies. Fit a compact (50/34) or sub-compact chainset paired with a wide-range cassette — a 34×32 or 34×34 bottom gear gives you a spinnable escape on the sharpest pitch without grinding. Check your setup before the ride: confirm the cassette and rear derailleur can actually handle your largest sprocket, and that shifting is clean under load. A missed shift on a steep ramp is where undulating climbs punish you.

Summary

• Length: 12.8 km
• Average gradient: 3.56%
• Maximum gradient: 19.75%
• Net elevation gain: 457 m
• Total ascent: 810 m
• Category: 3

Collado de Arichulegui looks gentle at 3.56% average, but 810 m of total ascent over a 457 m net gain tells the real story. Pace by effort, gear for the steep ramp, and respect the undulation.