Above the treeline the path often fades into a braid of sheep tracks, then into nothing. Off-trail in forest or tundra there was never a path to begin with. In both cases navigation stops being a matter of following and becomes a matter of choosing: which line across the ground is easiest to hold, easiest to check and hardest to get wrong. Three techniques from the orienteering world, handrails, catching features and aiming off, provide most of the answers, and they are best understood as ways of designing a route so that our inevitable errors do not matter.
Designing a route around error
Every leg we walk has an error attached: a few degrees of bearing drift, a few percent of distance, a small misreading of where we started. The unskilled approach is to try harder to be accurate. The skilled approach is to accept the error and shape the route so that it is caught before it costs anything. That means choosing legs that end at big, unmistakable things rather than at points, and choosing lines that follow something rather than crossing empty ground on faith. Off-trail, the direct line is rarely the best one.
Handrails: things to walk beside
A handrail is any linear feature that runs roughly in the direction we want to go: a stream, a ridge crest, a lake shore, the edge of a forest, a wall, a line of cliffs, a change in vegetation, the base of a scree slope. We do not need to walk on it, only to keep it within sight or sound on one side. As long as the stream is on our left, we cannot be far wrong, and we can move quickly without checking the compass every minute.
Contour lines themselves make a handrail. Walking a contour, keeping the same height across a slope, holds us on a line that the map defines exactly, and it is often the most energy-efficient way around a hillside. The technique needs an altimeter or an attentive eye: the ground should feel neither uphill nor downhill underfoot. In snow or fog, a contour traverse across a convex slope needs particular care, because the steepening below cannot be seen.
Good route planning strings handrails together. From the col, follow the ridge north to the flat shoulder; from the shoulder, follow the stream down to the lake; from the lake, follow the shore to the outlet. Each handrail hands us to the next, and the compass legs in between are short.
Catching features: the line that says stop
A catching feature, sometimes called a collecting feature or a backstop, is a large feature beyond our target that we cannot miss and cannot cross without noticing. A river, a road, a cliff edge, a sudden change from moor to forest, a wide col. If our target is a small tarn and the ground beyond it drops to a river 300 m further on, the river is our catching feature: reaching it tells us unambiguously that we have overshot, and by roughly how far.
The value of a catching feature is that it bounds the search. Without one, walking past the tarn in mist leads to an open-ended wander with growing doubt. With one, the moment our boots touch the riverbank we turn around, and the tarn is somewhere in the 300 m we have just walked. Choosing legs with a catching feature is often worth a detour of several hundred metres. A leg that ends in featureless ground with nothing behind it is a leg to redesign.
Attack points do the same job in miniature. Rather than aiming a long bearing at a small target, we aim at a large, easily found feature close to it, a pond, a knoll, a stream junction, and then take a short, careful bearing from there. The long leg can be sloppy; the short one is precise.
Aiming off: choosing to be wrong on purpose
Suppose the target is a footbridge over a stream that runs across our path. If we take a bearing straight at the bridge and walk 1 km through fog, we will arrive at the stream with a lateral error of perhaps 50 to 90 m, and we will not know whether the bridge is to the left or the right. Half the time we will guess wrong and walk away from it.
Aiming off solves this by deliberately setting the bearing 5 to 10 degrees to one side of the bridge, say to the left. Now when we reach the stream we know with certainty that the bridge is to the right, and we simply turn and follow the bank until we find it. We have converted an unknown error into a known direction. The same trick works for a hut on a ridge, a gate in a wall, a path junction on a forest edge, any point target that lies on a linear feature. The linear feature becomes a handrail that leads to the point, and the compass leg only has to reach the line, not the point.
The angle to aim off depends on the leg. On a long leg with poor visibility, 10 degrees is sensible; over 1 km that puts us about 175 m to one side, comfortably beyond our likely drift. On a short leg in good visibility, 3 to 5 degrees is enough. Aiming off too generously merely adds walking along the handrail; aiming off too little reintroduces the ambiguity.
Reading the ground itself
Off-trail terrain carries its own information. Above the treeline, animal tracks tend to follow the easiest line across a slope, and a well-worn trod is worth following even when it wanders from the bearing. Vegetation marks water: the deep green of sedge and moss below a spring, the abrupt end of dwarf shrubs at a scree edge. Rock type changes the walking and often shows on the map as a change in contour character, from smooth rounded lines on softer rock to jagged ones on harder. In forest, the map’s marked rides and firebreaks are reliable handrails, while the dense stuff between them can slow a party to well under 1 km/h and should be crossed only where a catching feature waits on the far side.
Putting the toolkit together
A well-designed off-trail leg answers four questions before we take a step: what will we walk beside, what will stop us if we overshoot, what large feature near the target will we aim at first, and which side of the target will we deliberately favour. The habits that make it work on the hill are simple:
- Plan legs from feature to feature, not from point to point in empty ground.
- Prefer a longer route along a handrail to a shorter one across nothing.
- Name the catching feature for every leg; if there is none, change the leg.
- Aim off whenever the target sits on a line, and remember which side you chose.
- Confirm each arrival with two features before starting the next bearing.
Practised this way, off-trail navigation stops feeling like a test of nerve and starts feeling like carpentry: we measure, we leave a margin, and we cut to the line.