Alto de Chaco

Alto de Chaco cycling climb profile

Alto de Chaco is a compact but serious category 1 climb in Bolivia: 8.9 km long, 8.23% on average, and rising from 677 m to 1413 m. The raw numbers already tell the main story. This is not a long alpine grind where the difficulty comes from distance alone. It is a sustained, steep ascent where the average gradient is high enough to punish poor pacing, and the maximum gradient of 22.68% means there are sections where momentum and gear choice matter as much as aerobic strength.

The climb gains 736 m net, with 749 m of total ascent. That small difference between net gain and total ascent points to a route that is mostly uphill rather than one broken up by meaningful downhill recovery. In practical terms, once the climb starts, expect very little help from the road.

How the gradient rides

With an average of 8.23% across 8.9 km, Alto de Chaco should be treated as a sustained effort from the bottom. The climb is steep enough that riding above sustainable power early will not be easy to repair later. Even if the road briefly eases, the overall profile gives back very little free speed.

The defining feature is the spread between the average gradient and the 22.68% maximum. An 8.23% average already sits in the range where seated climbing becomes a controlled strength effort. A ramp above 22% changes the ride entirely: cadence can collapse, traction becomes more relevant, and any rider already close to limit will be forced into repeated anaerobic spikes. The key is not to chase speed on the steepest pitches. The goal is to keep the effort from turning into a series of surges that leave you empty before the summit.

Pacing strategy

Ride the first part slightly below your target climbing effort, especially if you are pacing by /glossary/ftp. On a climb this steep, the cost of an early overreach is amplified because there are few easy sections to clear fatigue. If you are using power, cap the surges on the hardest ramps rather than trying to hold a perfectly even number. If you are riding by feel, the correct sensation early is controlled pressure, not fighting the bike.

The middle of the climb is where discipline matters. The average gradient means you will always be working, so settle into the lowest effort that still feels purposeful. Save any real acceleration for the final approach, when the remaining distance is no longer long enough for the 22.68% ramps to cause a pacing failure.

Gearing notes

Bring a low gear. Alto de Chaco is not a climb to over-gear for pride. The combination of 8.9 km, 8.23% average gradient, and ramps up to 22.68% makes a compact or sub-compact setup sensible for most riders. The right gear is the one that lets you stay seated through the sustained sections and absorb the steepest pitches without grinding yourself into repeated maximal efforts.

If you run out of cadence on the ramps, keep the bike smooth and avoid sudden accelerations. On a climb with 736 m of net gain, every unnecessary spike has to be paid back before the top.