Paso de Alceseca (Mazatlán) cycling climb profile
Paso de Alceseca (Mazatlán) is a category 1 climb in Mexico that asks for patience more than violence. On paper, the key number is the length: 20.2 km. At an average gradient of 4.72%, it is not brutally steep, but it is long enough that poor pacing early will show up clearly before the summit.
The climb starts at 498 m and tops out at 1,450 m, for 952 m of net elevation gain. That tells you the main character of the ascent: sustained upward pressure rather than a short, punchy effort. The maximum gradient is 7.85%, so the hardest ramps are meaningful without turning the climb into a low-cadence grind by default.
How the gradient rides
With an average just under 5% and a maximum below 8%, Paso de Alceseca should ride as a controlled aerobic climb for strong riders and a long threshold-management test for anyone pushing the pace. The numbers suggest a climb where the danger is not one decisive wall, but the accumulation of time spent climbing.
That matters tactically. On a climb this long, the temptation is to treat the moderate average gradient as permission to ride too hard from the base. The better approach is to let the opening kilometres feel almost underwhelming. If the effort feels sharp early, it is likely too sharp. The climb has enough total elevation change that the final portion will reward the rider who has kept a lid on their effort.
Pacing and gearing notes
Use the 4.72% average as the anchor for pacing, but respect the 7.85% maximum. The ramps are not extreme, yet they are steep enough to push a rider above sustainable power if they arrive already loaded from the earlier kilometres.
Practical pacing:
- Start below target effort and build into the climb once the rhythm is established.
- Keep cadence smooth on the moderate sections instead of forcing a big gear.
- Treat any steeper ramps as short pressure points, not attacks against the climb.
- If riding by power, this is a good climb to cap effort relative to /glossary/ftp rather than chasing speed.
For gearing, most riders will want a range that allows comfortable cadence on gradients approaching 7.85% after a long build-up. Because the climb is more sustained than savage, the goal is not just having an emergency gear. It is having enough range to stay economical for the full 20.2 km.
What to expect
Paso de Alceseca is a climb where restraint is speed. Its category 1 rating is justified by duration and elevation gain rather than extreme steepness. Ride it evenly, avoid surging into the steeper pitches, and the profile becomes manageable. Misjudge the early pacing, and the same moderate gradients will start to feel much heavier near the top.