Overview
Long Tom Pass is a Category 1 climb in South Africa (ZA), running 16.3 km from a start elevation of 1,213 m to a summit at 2,148 m. Over that distance it delivers a net elevation gain of 935 m at an average gradient of 5.73%. On paper that average reads as a steady tempo climb, but the numbers underneath tell a more demanding story.
The gap between the net elevation gain of 935 m and the total ascent of 1,283 m is the detail that matters most. That 348 m difference is climbing you do twice — ground you gain, give back on descents or false flats, then have to reclaim. This undulation means the effort is punchier than a smooth 5.73% grind. You will repeatedly break and rebuild rhythm, and the extra vertical work is real fatigue that the net figure hides entirely.
How the Gradient Unfolds
The 5.73% average is a blend, not a constant. With a maximum gradient of 19.68%, there are pitches nearly three and a half times steeper than the average, and those ramps do most of the damage. Because the total ascent exceeds the net gain by 348 m, expect the road to roll rather than climb in one clean line.
- Flatter and recovery sections where the grade drops well below average, and short descents that give back some of the 348 m of extra ascent
- Repeated short climbs that interrupt any steady rhythm and force you to re-accelerate
- A steepest ramp touching 19.68% — the pitch that dictates your lowest gear
Pacing Notes
On a smooth climb, even-effort and even-speed converge. Here they do not. Chasing even speed over a rolling profile makes you overspend on every steep kick and coast the recoveries, spiking your cost. Instead, hold even effort: let speed rise on the flatter sections and fall on the ramps, keeping your output anchored to your sustainable power output rather than the terrain. Absorb the 348 m of repeated climbing by keeping the steep pitches controlled instead of attacking them. If you do not know your ceiling, run the FTP estimator first so your target watts are grounded, not guessed.
Gearing
Gearing is governed by the steepest gradient, not the average. At 19.68%, a standard setup will have you grinding well below cadence. Run a compact (50/34) or sub-compact chainset paired with a wide-range cassette — a 34×32 or 34×34 low gear gives you room to spin the steep ramps without overloading your knees or blowing past threshold. Check your setup before the ride: confirm the cassette is actually fitted and the rear derailleur handles the largest sprocket cleanly.
Summary
- Length: 16.3 km
- Average gradient: 5.73%
- Maximum gradient: 19.68%
- Net elevation gain: 935 m
- Total ascent: 1,283 m
- Category: 1
Long Tom Pass rewards riders who respect the difference between its 935 m net gain and 1,283 m of total ascent. Pace to effort, gear for the 19.68% ramps, and the undulation becomes manageable rather than punishing.