23/08/2026
Here’s post 3 of 3 covering useful ways your compass can be helpful even in situations where you're not following a bearing or doing triangulation. (Anyone who has signed up to our newsletter has already seen this. Sign up at our website if you want first access next time!)
HOW TO USE CONTOUR LINES WHEN YOU ARE HEADING STRAIGHT DOWN
An important rule is that if you're facing straight down or straight up a slope and extend your arms out to your sides, your arms are aligned with the contour lines on the map. Another way of saying this is that if you're traveling either directly downhill or directly uphill, you're traveling exactly perpendicularly to the contours.
Imagine you're planning a descent through untracked bush from Hut Spur down to the north. You left the ridge where it changes direction about halfway between points 1581m and 1545m, and you've descended to the bushline near the crest of the prominent spur, above points A and B.
Your plan is to simply bomb down until you're at 1100m, where there will be a noticeable easing of the gradient. From there you'll swing north-west until you encounter a steep drop-off towards Jordan Stream; you'll turn right and keep that drop-off on your left as a handrail as you descend the final spur to the valley just west of Birch Nook. It's a good plan.
Less than half an hour after you start your descent, things don't seem right. It's getting REALLY steep in front of you. That's not supposed to happen. It turns out that when you started going straight down through the bush, you weren't at point A; you were just a tiny bit east of the crest of the spur, at point B. Look closely at the contour lines there: if you travel perpendicularly to them, you're going to be flung off further east than your planned route, straight into the jaws of the "BUG" (big ugly gully).
Nuances of the contours like that can have a big impact. To confirm where you are next time, point your compass in the direction the slope is falling. At point A this would be almost due north; at point B it would be about 035 degrees. The latter would make you realise you're too far east, and a quick easy sidle now while you're still high will save a ton of energy later. You can also use this method when sidling around a hillside, to determine how far you've gone simply by determining in what direction the slope is falling.
**** Want to learn more? Spaces still available on courses from late August to late September.
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