Poor Visibility Navigation Tips Part 1

Updated: Nov 20

I get asked a lot of questions about the poor visibility navigation element of the Mountain Leader Award, generally folk get a little anxious about this part. I fully understand this, as cloud or darkness descends, everything changes, your sensory perception of everything around you, your situational awareness, shadows become new contour lines, a piece of rock becomes an outcrop, a small drop becomes a cliff…..

It’s almost unnerving in many respects and takes time to build up the confidence to be in this type of situation.

A word that I’ll use a lot throughout this is confidence. Whatever the situation, you need to have confidence in which technique to choose and how to apply it and importantly confident in those conditions. It’s born from experience, it’s about having a go, going out on days that are less than ideal, trying different techniques in different terrain, reflecting on the mistakes you make and so on, I often refer to this learning as your ‘apprenticeship’. I look back and think of of all the all the times I’ve just wandered around somewhere in poor conditions and haven’t really had a clue where I was, I appreciate that time though, it made me more comfortable with being in that position, it doesn’t worry me about being in bad visibility or darkness. In a twisted way I quite enjoy it, that’s not to say though that I’m relaxed, often I’m in a more heightened state, switched on and working hard.


There’s a great C.S Lewis quote,

‘Experience is that most brutal of teachers. But you learn, my god you learn.’


There are no short cuts to getting this experience, you have to to go out and have a go…..However you can do this in a progressive manner which will build your knowledge, skills set and confidence. On my ML training courses I run 2 night navigation sessions, the 1st in an easy area, refining measuring distance and bearings and then applying those on the ground accurately. The 2nd night out takes this a stage further and whilst continuing with the basic techniques, we apply them in a more complex terrain and look at some additional tools to aid us in this environment.


There are lots of things that could go wrong, for me being comfortable in that environment is crucial, the more settled you are in poor visibility or darkness the less likely a mistake will be made. Under stress, accurate bearings and distances from the map can quickly go awry, walking on a bearing is executed ineffectively, pacing is not adapted to the terrain and any form of relocation becomes a wander around looking for things that never really materialise. Certainly a Mountain Leader assessment will be challenging performing like this, beyond though is real clients and at that stage you can’t be making those types of errors.


In poor visibility we need to rely on a few key techniques, the skill is in choosing the right one for any given situation. Direction and Distance are the 2 most likely skills that we’ll use.


I’ll lay out some simple ideas covering terrain, distance and some sneaky tips around seeing the fine detail on the map…


Firstly visit somewhere that is not to complex and which has a range of good features in a small area, this area at the northern end of Cwm Idwal for example is an excellent location. It has lots of great features, both natural and man made (which are pretty accurate in this instance), short distances between them all and relatively good terrain underfoot rather than anything awkward.

It makes a lot of sense to practise all these techniques in daylight in good conditions, it’s comfortable, you can see everything, if you make mistakes it easier to work out the reasons why and so on. You could then revisit the same area at night, you have familiarity with the objectives, so this will help with your confidence in whether you’ve arrived or not, maybe try to find the same objectives, but from different starting points.


Visit new areas that are similar, again in daylight, get some time under your belt practising all your techniques. As and when you can then move it on, eventually the ultimate challenge is to head into complex terrain that is unknown to you in darkness. Hopefully a nice progressive pathway rather than thinking that heading into the Moelwyns for some night navigation is the only way!


Measuring distance off the map is a crucial skill and one which you need to be able to do accurately. Timings and pacing are the 2 techniques we use and for short distances I find pacings over ground that isn’t steep or particularly awkward to be very accurate, I passed my Winter ML in 2006, I paced everything, 5 days of just counting in poor visibility sent me delirious, I timed lots of legs, but my pacings were the key. However someone else on the course timed everything, 100m or 1000m and he was incredibly accurate, hardly pacing anything, so it’s a choice you make.


If you haven’t already, then calibrate your paces, make sure you know who many you do to a 100m. Access to a running track is a fantastic way to do this, if you climb then using a 50m climbing rope could also work well, maybe try it with your rucksack as it may affect your normal walking stride. Once you’ve worked out what your pace count for 100m on the flat is then you can divide it down to 50m and 25m.


There are 2 ways to measure distance, one is to use the roma and the measuring tool in mm is the other option. You will have a higher level of accuracy with the mm, so for short distances this will be more beneficial.

Converting mm to meters is very straight forward, however doing mental arithmetic when you’re tired and wet is always going to be challenging. Use ‘pacing cards’, it’s pretty simple, put whatever info on them that you want and use them - you’ll get familiar with the numbers, don’t make simple mistakes doing maths!

Now we need to apply that distance to the ground. There are lots of good exercises, creating shapes is one of them, whether squares, triangles or hexagonal, as always try it in daylight first. Start small like 50m and next to a recognisable feature, then walk that distance on a northerly bearing, switch to east and then walk another 50m and so on until you complete the square, you can use any number, just add 90’ each time. For triangles it’s 120’ and 60’ for hexagons.

These will force you to walk up, across and down terrain, so will help you understand how your stride is affected and therefore your pace count. Again you could progressively challenge yourself by making the shapes larger and then then in poor visibility or darkness. You will also find the limitations to pacings.


Using your non complex area you’ve identified, have a look for any linear features like boundaries or streams on the map - look for ones that have bends in / junctions with distances of 50 /100/ 200m between them- you can then measure off the map and then apply the paces on the ground.


You could experiment with these on slightly steeper ground and see how that affects your stride and pace number. You’re most likely to come up short, so start your count from 0 and count to your objective, this will give you additional paces, so for example 10 paces. This means that next time you’re on similar terrain that you know you’ll need to add another 10 paces to every 100m you walk.


Another option on awkward ground when you’re pacing is to adapt your count as your stride changes. So for example, photo left shows my normal stride and photo right my stride has changed because of the ‘terrain’ - in this instance I may choose not to count.

At times you may be short, with time and practise in different terrain you will build the knowledge of what additional paces you will need to add in the future when on similar terrain. With all these type of exercises some form of a GPS or mapping on your phone helps with the distance travelled - check the accuracy of the unit you’re using - it can also track your route and so will help you identify what happened on the journey if needed.


On a side note I get asked a lot about sneaky tips for reading the minute detail of a map in the dark, in heavy rain, while wearing glasses, it’s a good question! Consideration on a personal level will depend on whether you prefer glasses or contact lenses, but you need to make sure you have a good wired hood on your waterproof or use a baseball style cap - it’s all about a good peak that protects your glasses / face. A lot of waterproofs will have some type of a ‘stiffened’ hood, some clearly are not designed for a wet and windy UK mountain day, so it’s wise to consider this before you buy. Use the magnifier on the compass or invest in a better one, I’ve seen a Sherlock Holmes type being used very effectively before and also small ‘credit card’ size ones are regularly brought out - some of these come with a small light attached to them as well. Annotate maps to help keep your location - sharpies, chino-graphs all work, although only the latter in wet conditions. It’s very hard to see the detail on any map in poor light conditions, add a little rain and some wind in and it can be very challenging, so if you use mapping software, experiment to see if you can blow up the scales to print. So for example I can print 1;25k at a scale of 1;10k, you obviously need to check the measurement of the grids are correct and colours and so on. There is no need to struggle to see the map these days!

As I said at the beginning, there are no shortcuts to gaining the knowledge to be confident in this environment, practise is the key….


Next time, I’ll visit taking / walking on a bearing and some ideas of how to relocate….

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