Puerto de Ancares

Overview

Puerto de Ancares is a Category 1 climb in Spain, running 10.2 km from a start elevation of 819 m to a summit at 1,673 m. The net elevation gain is 854 m, and the average gradient across the ascent sits at a demanding 8.34%. That combination — over ten kilometres of climbing at better than 8% — puts it firmly in the territory where the climb dictates the ride rather than the other way around.

The number that reveals the real character here is total ascent: 1,216 m, against a net gain of only 854 m. That 362 m difference is descending you have to pay for twice, because every metre you drop mid-climb is a metre you have to reclaim on tired legs. Ancares is not a smooth ramp — it undulates, and that undulation means your legs absorb roughly 40% more vertical than the net figure suggests. Budget your effort against 1,216 m, not 854 m.

How the Gradient Unfolds

An 8.34% average is a blend, not a constant. On a climb with this much undulation, the average masks both the recovery dips and the ramps that spike well above it — including a maximum pitch of 22.62%, steep enough to force you out of the saddle or into your lowest gear on the spot.

• Flatter and false-flat sections where the road eases and you can spin to recover
• Short descents mid-climb that break rhythm and add to total ascent
• Repeated punchy ramps that keep pulling the gradient back above average
• A maximum pitch of 22.62% — the single hardest moment, and where an over-geared setup will hurt most

Pacing Notes

On an undulating climb, even-speed pacing is a trap: holding a fixed speed means overcooking the steep ramps and coasting the flats. Pace to effort instead. Anchor your climb to your sustainable power output and let speed vary — push a shade below threshold on the ramps, ease genuinely on the recovery sections rather than chasing the clock.

Because the ramps hit 22.62%, brief surges above threshold are unavoidable; keep them short and controlled so you are not paying interest for the rest of the climb. If you do not know your current threshold, run the numbers through the FTP estimator before you ride and set a ceiling you can hold for the full 10.2 km.

Gearing

The steepest pitch — 22.62% — governs your gearing choice, not the average. A standard chainset will leave you grinding a cadence that shreds your legs on those ramps. Fit a compact (34-tooth inner) or sub-compact chainset paired with a wide-range cassette, something like a 34×32 or 34×34, so you have a bailout gear for the 20%-plus sections. Check your chainrings and cassette before the ride — confirm the setup on the bike matches what these ramps demand, not what you assume is fitted.

Summary

• Length: 10.2 km
• Average gradient: 8.34%
• Maximum gradient: 22.62%
• Net elevation gain: 854 m
• Total ascent: 1,216 m
• Category: 1

Puerto de Ancares rewards riders who respect the gap between its net gain and its total ascent. Pace to effort, gear for the 22.62% ramps, and treat the 1,216 m of climbing as the real workload — do that, and the summit at 1,673 m comes to you.