Selletta di Bobbio

Overview

Selletta di Bobbio is a hors catégorie climb, the hardest rating there is, and its numbers explain why. Over 16.5 km the road lifts you from a start elevation of 198 m to a summit at 1576 m, a net gain of 1378 m. The average gradient sits at a punishing 8.35%, which on a climb this long is already a serious day out. What tips it into HC territory is the maximum pitch of 29.23%, a wall steep enough that momentum, gearing, and pacing all have to be managed with care. This is a climb you respect from the bottom, not one you attack.

How the Gradient Unfolds

An 8.35% average across 16.5 km is relentless rather than merely hard. If the entire climb held that grade evenly, you would simply settle into a rhythm and grind. But the gap between the 8.35% average and the 29.23% maximum tells you the road is far from uniform. Those steepest ramps drag the average up, which means there are also shallower stretches where you can recover, breathe, and reset before the next kick. The total ascent of 1306 m is slightly less than the net elevation gain of 1378 m, a sign the profile is almost entirely uphill with little to no descending relief along the way. Plan for the pitches, not the average.

Pacing Notes

On a 16.5 km HC climb, discipline beats bravado. The single most useful number you own here is your FTP, your functional threshold power. Ride the sustained sections at or just below it, and save your matches for the 29.23% ramps where staying upright and turning the pedals is the only goal. Going too deep early on a climb with 1378 m of vertical gain is how riders blow apart with kilometres still to go. If you do not know your threshold, estimate it first with the FTP estimator, then work backward to a target you can hold from bottom to top. Fuel and drink on the shallower recovery stretches, because on the steep pitches you will have neither the hands nor the breath to spare.

Gearing

Do not undergear this one. A maximum gradient of 29.23% will overwhelm any setup built for rolling terrain, and 16.5 km of climbing at 8.35% average means you will be in your easiest gears for a long time. A compact 34-tooth chainring paired with a wide cassette is the sensible baseline. A 34×32 is the minimum most riders should consider here, and even strong climbers will be glad of a 34×34 when the road rears up toward 29.23%. If your bike accepts an even larger cassette, take it. Spinning a low gear at a survivable cadence protects your legs across the full 1378 m of ascent far better than muscling a gear that is too tall.

Summary

Selletta di Bobbio is a genuine HC test: 16.5 km, 8.35% average, 1378 m of net elevation gain, and a 29.23% maximum that demands proper gearing and a patient head. Pace it to your threshold, gear it low, and treat the steep ramps as survival rather than performance.

Length: 16.5 km
Average gradient: 8.35%
Max gradient: 29.23%
Start: 198 m
Summit: 1576 m
Net gain: 1378 m
Total ascent: 1306 m
Category: HC