Paso de Mariposas

Paso de Mariposas cycling climb profile

Paso de Mariposas is a short, measured Category 4 climb in Chile, rising from 820 m to 967 m over 3.6 km. On paper, the defining feature is restraint: the average gradient is 4.09%, and the maximum gradient is 6.03%. That combination tells you this is not a climb built around a decisive wall or a single violent pitch. It is more of an aerobic pressure test, where the cost comes from riding a steady tempo and resisting the temptation to treat the lower gradient as free speed.

The net elevation gain is 147 m, while the listed total ascent is 133 m. In practical riding terms, the climb is still best approached as a continuous uphill effort rather than a punchy, stop-start ascent. With a summit elevation of 967 m, the profile is high enough to feel like a proper pass, but the numbers point to a climb where pacing discipline matters more than survival gearing.

How the gradient unfolds

Across 3.6 km, a 4.09% average means the road should feel manageable from the bottom, especially for riders who are comfortable holding steady pressure below threshold. The key detail is the 6.03% maximum gradient. That ceiling keeps the climb within a narrow tactical band: the steeper moments are enough to punish a lazy gear choice, but not steep enough to force repeated accelerations if you are already riding smoothly.

This makes Paso de Mariposas the kind of climb where speed can be deceptive. Because the gradient is moderate, it is easy to start too hard, especially if the first part feels comfortable. The problem is that a short climb still lasts long enough for an over-threshold opening to show up near the top. If you are using /glossary/ftp as a pacing anchor, this is the profile where a controlled effort just under or around sustainable climbing power will usually beat a surging approach.

Pacing and gearing notes

The cleanest way to ride Paso de Mariposas is seated, smooth, and slightly conservative through the opening section. Let the gradient come to you. Since the steepest recorded pitch is 6.03%, there is no need to save an emergency gear for a severe ramp, but you should still avoid grinding. A comfortable cadence will matter more than brute torque.

For a fast ascent, build the effort in three phases:

• Settle in early and avoid chasing speed on the gentler gradient.
• Hold a steady tempo through the body of the climb, using the moderate average to stay controlled.
• Lift the effort late once the summit elevation of 967 m is within reach.

For training, this climb suits tempo work, controlled threshold efforts, or repeatable climbing intervals. It is not steep enough to be a pure strength climb, and it is not long enough to become a deep endurance test on its own. Its value is precision: choose the right gear, keep the pressure constant, and make the final part the fastest part rather than paying for an impatient start.