Simplon Pass

What to Expect on the Simplon Pass

The Simplon Pass is a category 1 Alpine climb sitting on the Swiss-Italian border, starting at 1,315m and topping out at 1,999m. The net elevation gain is 684m across 10.5km, giving an average gradient of 6.54% — numbers that look manageable on paper until you account for the total ascent of 1,360m. That figure tells you the road is not a clean ramp. It rolls, kicks, and recovers repeatedly, which means your legs absorb considerably more work than the net gain suggests.

The maximum gradient of 30.24% is not a misprint. Somewhere on this climb the road tilts to a pitch that will force even experienced climbers to question their gearing choices. At that angle, traction and cadence collapse simultaneously if you are not prepared.

How the Gradient Unfolds

The average of 6.54% is best understood as a floor, not a ceiling. With a max of 30.24% and total ascent nearly double the net gain, the profile is clearly broken up by flatter or downhill sections that reset the legs — but those recoveries are followed by ramps that punch well above the average.

Key characteristics to anticipate:

• Lower slopes: Starting at 1,315m, the early kilometres establish the rhythm. Use this section to settle into a sustainable pace rather than chasing a fast opening split.
• Mid-climb variability: The gap between net gain (684m) and total ascent (1,360m) confirms significant elevation fluctuation through the middle portion. Resist the temptation to hammer the descending or flat sections — you will need that energy.
• Upper ramps: The closer you get to the 1,999m summit, the less margin for error. Any ramp approaching double-digit gradients at altitude demands a controlled power output relative to your FTP.
• Maximum gradient section: At 30.24%, this is an outlier that demands respect. It is unlikely to last long, but it will spike your heart rate and drain glycogen rapidly if you attack it rather than grind through it.

Pacing Strategy

The total ascent of 1,360m against a net gain of 684m is the most important number for pacing. You are not riding 10.5km at 6.54% — you are riding a lumpy, punishing route where the cumulative work is roughly double what the headline stats imply.

Recommended approach:

• Set your effort ceiling at or below threshold power from the first kilometre. Going over threshold early on a climb with this much variability creates debt you cannot repay.
• On false flats and brief descents, reduce power deliberately rather than spinning easy — active recovery beats passive coasting when ramps are coming.
• Before the maximum gradient section, drop a gear earlier than feels necessary. At 30%+, there is no room to shift once momentum dies.
• Budget for a hard final few kilometres to the 1,999m summit. Altitude is a factor from the start elevation of 1,315m upward — aerobic capacity decreases as you climb, even if the gradient temporarily eases.

Gearing Notes

A 30.24% maximum gradient at altitude is the deciding factor here. If you are running a compact chainset (50/34), pair it with at least a 32-tooth rear sprocket, preferably 34. On a standard (53/39), a 34-tooth or larger cassette becomes close to mandatory unless you are carrying significant climbing power. Riders who use a 1x drivetrain should confirm their low gear before attempting this pass — running out of gears on a 30% ramp with no momentum is a balance and muscle problem, not just a fitness one.

Use the FTP estimator to calculate realistic power targets before you set foot on this climb. Understanding where your threshold sits relative to the demands of 1,360m of total ascent is the single most useful preparation you can do.