Rengg

Overview

Rengg is a Category 2 climb in Switzerland, running 7.8 km from base to top. Over that distance it delivers a net elevation gain of 418 m, starting at 546 m and topping out at a summit elevation of 964 m. On paper it reads as a mid-tier ascent: long enough to matter, short enough to stay within reach of a rider who paces it honestly.

The number that reshapes the effort is total ascent. Rengg climbs 514 m in total against a net gain of only 418 m, meaning roughly 96 m of that height is given back and re-earned along the way. That is undulation, not a smooth drag to the top. Every metre you lose on a dip is a metre you have to reclaim, usually at a steeper grade than the average suggests. Expect your effort to spike and settle repeatedly rather than hold a single steady tempo.

How the Gradient Unfolds

The average gradient of 5.35% is an honest summary of the whole climb but a poor guide to any single moment on it. With 96 m of undulation baked in, the flatter and downhill sections drag the average down, which means the climbing pitches sit well above 5.35%. The steepest ramp reaches 21.58% — a wall that demands you are already in your lowest gear before you hit it.

• Flatter and recovery sections where the road eases or briefly descends
• Repeated short climbs stacked back to back, each steeper than the stated average
• A single steepest ramp near 21.58% that decides your gearing choice

Pacing Notes

On a smooth climb, even-effort and even-speed pacing converge. On Rengg they do not. Chasing an even speed across the undulations will push you far over your sustainable power output on every ramp and waste energy coasting the descents. Pace to effort instead: hold a steady, controlled power on the climbs and let your speed rise and fall with the terrain. Accept that you will slow on the 21.58% pitch — grinding over it below threshold beats blowing up above it.

Know your ceiling before you start. Run the FTP estimator so you have a concrete number to pace against rather than guessing on the day.

Gearing

The 21.58% maximum gradient governs your setup, not the 5.35% average. That ramp will over-gear a standard chainset and force you to stand and heave. Fit a compact or sub-compact chainset paired with a wide-range cassette — a 34×32 or 34×34 gives you a bailout low enough to spin the wall seated. Check your chainset and cassette before the ride; discovering you are one gear short at 21% is a mistake you make only once.

Summary

• Length: 7.8 km
• Average gradient: 5.35%
• Maximum gradient: 21.58%
• Net elevation gain: 418 m
• Total ascent: 514 m
• Category: 2

Rengg rewards riders who respect its undulation. Pace to effort, gear for the steepest ramp, and its 418 m of net gain will feel earned rather than survived.