Grubenpass

Overview

Grubenpass is an HC-category climb in Switzerland, running 11.7 km from a start elevation of 665 m to a summit of 2,182 m. Over that distance it delivers 1,517 m of net elevation gain at an average gradient of 13.02%. That average alone tells you this is not a climb you ride into unprepared: sustained double-digit gradients over nearly 12 km put Grubenpass among the hardest paved efforts you will find, and the HC label is earned rather than generous.

The number to watch is the gap between net gain and total ascent. You climb 1,517 m net but accumulate 1,902 m of total ascent, which means roughly 385 m of that elevation is lost and re-climbed along the way. Grubenpass is not a clean, monotonic ramp. That extra 385 m of undulation adds work your legs feel but the net figure hides, and it changes how you should pace and gear for the effort.

How the Gradient Unfolds

A 13.02% average across 11.7 km is a warning, but averages smooth over the real shape of the road. Because total ascent runs 385 m above net gain, some of the profile dips or flattens, which means the climbing sections between those dips must run steeper than 13% to keep the average where it is. Expect sharp compressions rather than a steady wall.

• Short recovery or flatter sections where the road briefly eases or drops, contributing to the 385 m of extra ascent
• Repeated stacked pitches that re-climb lost elevation, each one steeper than the average implies
• A steepest ramp that spikes well above 13%, demanding a hard, deliberate gear change

Pacing Notes

On an undulating climb like Grubenpass, chasing an even speed will destroy you: holding a constant pace up the steep ramps forces surges far above your limit. Pace to even effort instead, anchoring to your sustainable power output and letting your speed rise and fall with the gradient. Bank nothing on the flatter dips; use them to recover, not to attack. If you do not know your ceiling, run the FTP estimator first and set a wattage target you can defend for the full 11.7 km. The 385 m of re-climbed elevation punishes riders who spend early.

Gearing

Gearing on Grubenpass is dictated by the steepest ramp, not the average. Sustained grades above 13% over this length mean a compact or sub-compact chainset paired with a wide-range cassette is not optional. Aim for at least a 34×32, and prefer a 34×34 to keep your cadence up when the road kicks. Check your setup before the ride: confirm your rear derailleur clears the largest sprocket and that the chain length is right for the big cog. Discovering you are over-geared halfway up an HC climb is a walk to the summit.

Summary

• Length: 11.7 km
• Average gradient: 13.02%
• Net elevation gain: 1,517 m
• Total ascent: 1,902 m
• Category: HC

Grubenpass is a short but uncompromising HC climb: nearly 12 km at over 13%, with 385 m of hidden re-climbing stacked on top. Pace to effort, gear low, and respect the undulation and it rewards you at 2,182 m.