Col de Port

Overview

Col de Port is a Category 2 climb in the French Pyrenees, running 11.5 km from its base at 666 m to a summit at 1247 m. The net elevation gain sits at 581 m, but the total ascent figure of 1372 m tells a different story — this is not a clean, uninterrupted grind. Undulations along the route mean you are doing considerably more work than the net numbers suggest, and that surplus effort will compound fatigue if you burn matches too early.

The average gradient of 5.05% is moderate on paper, but that figure is distorted by flatter and even slightly downhill passages. Strip those out, and the hard sections hit significantly harder — as evidenced by the 32.75% maximum gradient, one of the sharper ramps you will encounter on a categorised climb anywhere in France.

How the Gradient Unfolds

The lower slopes out of the valley floor are the most forgiving section of the climb. The road settles into a manageable rhythm through the initial kilometres, giving you time to find your FTP-appropriate pace before the terrain forces the issue.

As you progress through the mid-section, the gradient becomes more variable. Expect repeated sequences of steeper pitches followed by brief recoveries. This accordion effect is where most riders go wrong — surging on the kicks and then crawling through the easier stretches rather than maintaining a controlled, consistent output.

The maximum ramp of 32.75% is an outlier, not a sustained feature, but it is steep enough to force almost any rider out of the saddle and into full-effort territory. Identify it early on your descent recon or via a GPS profile, and approach it with enough momentum and gear reserve to get through without stalling.

Gradient Summary

• Length: 11.5 km
• Average gradient: 5.05%
• Maximum gradient: 32.75%
• Net elevation gain: 581 m
• Total ascent: 1372 m (significant undulation throughout)
• Category: 2

Pacing Notes

The gap between net gain (581 m) and total ascent (1372 m) is the key tactical fact on Col de Port. You will climb far more than the summit elevation difference implies. Build your effort budget around the total ascent figure, not the net.

Target a steady power output from the base. Given the category rating and the length, this is a climb where riding at or just below threshold for the duration is achievable for a trained rider, but the 32.75% ramp will spike effort regardless. Accept that spike, manage it, and return to your target power as quickly as possible rather than treating the hard pitch as a signal to push all the way to the top.

If you are using rate of perceived exertion or heart rate rather than power, keep the early kilometres conversational. Heart rate will lag on the steep ramps; trust your legs and cadence over the number on your screen through those sections.

Gearing Recommendations

The 32.75% maximum gradient is the governing factor for gearing selection. On a climb with a ramp this steep — even if it is brief — running out of gears is a genuine risk.

• Road bikes: A compact chainset (50/34) paired with an 11-32 or 11-34 cassette is the practical minimum. An 11-36 cassette with a wide-range derailleur gives more headroom.
• Gravel or adventure setups: A 1x drivetrain with a 40-tooth cassette or larger removes the problem entirely.
• Cadence target: Aim for 70–80 rpm on the moderate sections. On the maximum ramp, your cadence will drop regardless — gear down early, before the pitch bites, not during it.

If you are unsure where your fitness puts your optimal gearing, the FTP estimator can help you map effort to gradient and speed before you head out.

Bottom Line

Col de Port rewards patience and punishes optimism. The average gradient undersells the difficulty, the total ascent figure is the honest metric, and the maximum ramp demands a spare gear. Treat it as a rhythm climb with one serious interruption, pace accordingly, and it is a satisfying Category 2 tick.