Making a route card (leg plan)

Short legs limit errors. Each section ends at an unambiguous point you can recognise even in poor visibility – a path junction, a saddle, a stream confluence, a hut. There you confirm your position before starting the next leg. This way an error can affect at most one leg, not the whole trip.

For each leg you note: the direction (the map bearing and, if needed, converted to a compass bearing), the length, the height gained and lost, the estimated time and – for critical sections – a safe way out. Added together, the times show whether the trip fits into daylight. From this you get the turnaround time.

For estimating time there are rules of thumb that combine distance and height gain. The best known is Naismith's rule from the 19th century: a base time for the distance on the flat plus an allowance for every climb. Such rules are a start but not fixed values. Load, fitness, ground, weather and group size change the time considerably. It is best to measure your own times on trips and use them as your basis.

Choose legs short enough that you are sure to find the end of each one. In confusing terrain or with a risk of fog, prefer more, shorter sections. The leg target should be large and unambiguous; 'a small clump of trees somewhere on the slope' is hard to find in poor visibility.

Do not forget height gain – it often costs more time than distance. Always plan a buffer, because breaks, photo stops and small detours add up. A common mistake is magnetic declination: the difference between map north and magnetic north. If it is applied twice or not at all, the compass bearing will be off. Write on your card whether the values are map or compass bearings.

Most important of all is actually using the card on the way. Note the time at each leg point and compare it with the plan. If you are clearly slower than planned, that is an early warning – the turnaround time is getting closer, or something is wrong with the route.

A route card is especially worthwhile on trips where fog or darkness threaten, on off-trail sections and in groups where different people take turns navigating. It forces you to study the route at home – and many problems show up before you even set off.

You can give a copy of the card to a trusted person, together with your planned return time. Then, in an emergency, they know where you were going. The card's weakness is spontaneous route changes: if you change route on the way, you need to think through the new legs briefly, otherwise the card is no longer any use.

A line on the map says nothing about whether the terrain is safe to walk. Plan legs so that they avoid drops, water, avalanche and rockfall terrain, and turn back on the way when in doubt. A route card does not replace a weather and avalanche assessment, nor appropriate training in alpine terrain.

Stick to your turnaround time, even when the goal seems 'just there'. Many difficult situations arise because people overrun a turnaround time and then get caught by darkness, fatigue or bad weather. Better to miss a summit than spend a night outdoors without the right gear.

You need a topographic map, a compass with a ruler, a pen and paper – ideally an index card in a waterproof sleeve or a small notebook. Many people draw a simple table with columns for leg, direction, distance, height up and down, time and remarks.

Map apps calculate distance and height gain very conveniently. That is a good help when planning. Still take the key values on paper: a card needs no battery and works even when the phone is cold, wet or flat.