Relocating yourself: systematic instead of guessing

You rarely find a position from a single clue. You combine several independent traces, each uncertain on its own, which narrow each other down. The first clue is the last certain point. If you know how long you have walked since then and roughly your pace, you get a circle on the map: you must be somewhere inside it.

Then you look at the terrain. Are you on a slope, in a hollow, on a spur or in a saddle? Which compass direction does the slope face? Roughly how high are you? Each of these questions crosses out parts of the circle. A north-facing slope at roughly a certain height may fit only two or three places.

If you can see landmarks you can positively identify on the map – a summit, a radio mast, a church – you can take a resection. You measure the bearing to the landmark with your compass and draw the opposite direction (the back bearing) on the map from the landmark. With two or three such lines you get an intersection or a small triangle, the 'triangle of error' or 'cocked hat'. You are standing roughly there.

The hardest part is not the technique but your mind. When lost, people tend to 'bend the map': you talk yourself into believing the stream in front of you is the one you want, even if it flows the wrong way. Be honest with yourself. A feature that only half fits does not fit.

For a resection, choose only landmarks you are completely sure of. Ideally use two or three that lie in clearly different directions – then the lines cross at a good angle. If they lie in almost the same direction, the intersection becomes very imprecise. Remember to convert compass bearings to map bearings if magnetic declination matters in your area. A large triangle of error usually means a landmark is misidentified or a bearing is inaccurate.

A simple special case: if you are certainly on a known path or by a stream, a single bearing is enough. Where the bearing line crosses the path, that is where you are. Time notes along the way make all of this much easier. If you briefly note the time at every junction, you can later reconstruct much more precisely how far you can have come.

Systematic relocation is always worthwhile as soon as expected features fail to appear or you doubt your position – the earlier, the better. After ten minutes of uncertainty the search circle is small; after an hour of aimless walking it is huge.

But if the situation is acutely dangerous – someone is injured, a storm is coming, you are in fall terrain or it is getting dark – orientation comes second. Then first make yourself safe, keep warm and call for help. If you cannot work out your position, there are three sensible options: walk back along the known route to the last certain point, head for a large catching feature you cannot miss such as a road or a river, or stay where you are and let yourself be found. Which one is right depends on terrain, weather, your strength and the time of day.

A position on the map says nothing about whether the way there is safe. Even once you know where you are, the straight line to your destination may lead over drops, through water or through avalanche and rockfall terrain. Go around such places and turn back when in doubt.

Being lost is tiring and makes you nervous. Eat and drink something, dress warmly and make decisions calmly. If you are alone, or the group is anxious, it helps to say the steps out loud. And when you call for help, describe your last certain point and what you can see – that is very valuable for rescuers.

Practise resection at a viewpoint where you know your position exactly. Take bearings on two or three landmarks, draw the lines and see how close the intersection is to your real position. This gives you a feel for how big a normal triangle of error is.

A second good exercise: on a hike, let a companion lead you to a spot without you looking at the map. Then try to work out where you are using only terrain, slope direction and time. This exercise trains exactly what counts in a real situation: honest comparison instead of guessing.