Colláu de lo Foratón

Overview

Colláu de lo Foratón is a hors catégorie climb, the hardest classification on the scale that runs from HC down through categories 1, 2, 3 and 4. The reasons for that rating are written plainly in the numbers: 12 km of road at an average gradient of 9.4%, lifting you from a start elevation of 880 m to a summit at 2012 m. That is 1132 m of net elevation gain, with 1103 m of total ascent recorded along the way. When average gradient sits this close to double digits over a distance this long, there is nowhere to recover — this is a climb that asks for a steady, honest effort from the very first metre.

How the Gradient Unfolds

The headline figure is the 9.4% average, but averages hide the sting. With a maximum gradient of 20.08%, this climb has ramps that more than double the mean, and those are the sections that break a rhythm. The gap between the 9.4% average and the 20.08% max — nearly 11 percentage points — tells you the road is not uniform. Expect stretches that sit near or just under the average punctuated by short, savage pitches toward that 20.08% ceiling. Because net gain (1132 m) slightly exceeds total ascent (1103 m), the climb is almost relentlessly upward with negligible respite. Plan your effort around the steep ramps, not the average.

Pacing Notes

On a climb this long and this steep, pacing is everything. The single biggest mistake is going out hard on the lower slopes and paying for it above 1500 m of elevation. Anchor your effort to your FTP: aim to hold a power target you can sustain for the full 12 km rather than a heart-rate number that will drift upward as you climb. If you are unsure of your threshold, run the numbers through the FTP estimator before you commit to a target. On the 20.08% ramps, let your effort spike briefly above threshold — that is unavoidable — then settle back to your sustainable number as soon as the road eases. Over 1132 m of climbing, discipline early buys you legs at the top.

Gearing

Do not under-gear this one. With an average of 9.4% and pitches to 20.08%, a compact 34-tooth inner ring paired with a wide cassette is the sensible baseline. A 34×32 will get most fit riders up the sustained sections, but on the steepest ramps toward 20.08% you will be grinding at low cadence. For that reason, a 34×34 is the smarter choice for the majority of riders tackling 12 km at this gradient — the extra range keeps your cadence spinning and protects your knees on the walls. If your bike allows an even wider range, take it; there is no prize for suffering on gearing that is too tall over 1103 m of ascent.

Summary

Colláu de lo Foratón earns its HC badge honestly: long, steep, and unforgiving from 880 m to 2012 m. Come with climbing gears, a threshold-based pacing plan, and the patience to hold back on the lower slopes so you still have legs for the 20.08% ramps near the top.

Length: 12 km
Average gradient: 9.4%
Max gradient: 20.08%
Start: 880 m
Summit: 2012 m
Net gain: 1132 m
Total ascent: 1103 m
Category: HC