Colle di Arsines

Overview

Colle di Arsines is a long, steady category 1 climb that rewards patience over punch. It runs 14.6 km from an opening elevation of 591 m to a summit of 1371 m, delivering 780 m of net elevation gain across its length. The average gradient sits at 5.33%, which reads mild on paper but adds up relentlessly over nearly fifteen kilometres. This is a climb where the clock, not the slope, does the damage — few sections will overwhelm you, but the sheer sustained effort of holding a rhythm for the better part of an hour is what defines the day.

How the Gradient Unfolds

With a 5.33% average and a 12.11% maximum, Arsines is a climb of contrast. The gap between the mean and the peak tells you that the road is not uniform: long stretches near or below the average are interrupted by steeper ramps that spike toward that 12.11% ceiling. The total ascent of 727 m sits just below the 780 m net gain, a small but telling difference — it means the road climbs almost continuously, with barely any downhill or false-flat relief to break the effort. Expect to settle into a sustainable tempo on the shallower gradients, then absorb the sharper pitches without letting your cadence collapse. The steepest ramps are the moments to shift early rather than muscle through.

Pacing Notes

The key to Arsines is discipline in the first few kilometres. On a 14.6 km climb, the temptation to push above threshold on the opening slopes can cost you dearly on the ramps toward 12.11%. Aim to hold a steady percentage of your FTP — for most riders, sitting just under threshold keeps the effort repeatable across the full 780 m of ascent. If you are unsure of your numbers, run them through the FTP estimator before you plan your target power. Treat the average of 5.33% as your baseline pace, and bank a little reserve for the steeper pitches so you finish strong at 1371 m rather than crawling the final stretch.

Gearing

Given the 14.6 km length and pitches reaching 12.11%, gear conservatively. A compact chainring paired with a wide-range cassette is the sensible default here. A 34×32 will handle the sustained 5.33% sections comfortably and get most fit riders over the steeper ramps. If you carry endurance-day weight, expect heat, or simply prefer to spin, step up to a 34×34 for extra insurance on the pitches climbing toward the 12.11% maximum. On a climb this long, a slightly easier gear that protects your cadence almost always beats grinding a bigger one.

Summary

Colle di Arsines is a rhythm climber's mountain: long, steady, and demanding of consistent effort rather than raw power. Pace the opening kilometres, respect the ramps toward 12.11%, and let the 5.33% average carry you to the 1371 m summit.

Length: 14.6 km
Average gradient: 5.33%
Max gradient: 12.11%
Start: 591 m
Summit: 1371 m
Net gain: 780 m
Total ascent: 727 m
Category: 1