Colla Bassa

Overview

Colla Bassa is a category 1 climb in Italy that runs 18.4 km from a start elevation of 583 m to a summit at 1,601 m. Over that distance it delivers 1,018 m of net elevation gain at an average gradient of 5.52%. On paper that makes it a long, steady tempo effort — the kind of climb where fitness and pacing discipline matter more than raw punch.

The paper number is misleading, though. While the net gain is 1,018 m, the total ascent is 1,790 m — a 772 m gap. That means the climb repeatedly gives back elevation and forces you to reclaim it. You are not riding a single uphill ramp; you are riding a rolling profile with descents and false flats stitched into it. The practical effect is that your legs will do meaningfully more climbing work than the net figure suggests, and the descents rarely come as full recovery.

How the Gradient Unfolds

The 5.52% average is a blend, not a constant. Long stretches sit below that figure while short pitches spike well above it, topping out at a maximum of 25.4%. Reading the average alone will leave you under-geared and over-paced when the road kicks up.

• Flatter and recovery sections where the road drops or eases well under 5.52%
• Repeated short climbs that regain the elevation you just lost across the 772 m of extra ascent
• The steepest ramp reaching 25.4% — brief but severe enough to force you out of the saddle

Pacing Notes

On an undulating climb like this, chase even effort, not even speed. Holding a constant km/h means overcooking the steep pitches and coasting the descents — the worst of both. Instead, anchor to a target sustainable power output and hold it through the rollers, letting your speed rise on the shallow sections and fall on the ramps.

The descents built into the 772 m of extra ascent are not free rest, so don't bank on them to recover a blown effort. If you don't know your ceiling, run the numbers through the FTP estimator first and set a wattage cap you can defend for the full 18.4 km.

Gearing

The 25.4% maximum dictates your setup, not the 5.52% average. On pitches that steep, a standard chainset will grind you to a stall. Fit a compact or sub-compact chainset paired with a wide-range cassette — think 34×32 or 34×34 — so you keep a spinnable cadence when the road hits its steepest ramps. Check your chainset and cassette before the ride; discovering you are over-geared halfway up a 25% wall is not a problem you can fix on the road.

Summary

• Length: 18.4 km
• Average gradient: 5.52%
• Maximum gradient: 25.4%
• Net elevation gain: 1,018 m
• Total ascent: 1,790 m
• Category: 1

Colla Bassa rewards riders who respect the gap between its net gain and its total ascent. Gear for the 25.4% spikes, pace to power rather than speed, and treat the 772 m of hidden climbing as work you have to plan for — not a surprise.