When you’ve got a fully qualified and experienced International Mountain Guide in the office for a few days it seems criminal not to take advantage of his knowledge. So with Nick Parks on hand we decided to quiz him about the basics of navigation then link it in with a bit of advice on GPS and how modern technology can best fit in with traditional practices.
Quite simply, being able to navigate well is the cornerstone to safe and successful travel in the mountains. Not only could sound navigation literally save your life if you are out in bad conditions, knowing where you are at all times and being able to plan routes will make your trip to the hills an all round more enjoyable one. No matter how good you are at using your GPS, and they can be fantastic tools, there is no substitute for being able to use a map and compass. Good map reading is your passport to freedom in the hills.
Successful mountain navigation skills can be divided into two areas, pre-trip planning and actual navigation on the go. Every trip into the hills or mountains needs to be planned in advance to some extent, although critically route plans are never written in stone. Underpinning all trips in the mountains is the understanding that the mountain can never lose, and sometimes for all sorts of reasons you have to know when to turn round or amend your journey. If you are leading a group always monitor what affect the route and the conditions are having on the other members of the group (especially the weakest) and always be prepared to change plans before any problem becomes serious.
Normally pre-trip planning will require close study of the map and selecting a route. A key element in all pre-trip planning is estimating the time required to complete the route allowing for rest stops, etc. Planning needs to bear in mind the level of experience, aspirations and fitness of the party and consider numerous factors including; the difficulty and length of the route, the time of year, the weather conditions expected and prior knowledge of the route. Potential difficulties in route finding, and in particular, possible difficulties in finding the descent route at the end of the day when the party is tired, the amount of daylight available, and a good safety margin for unexpected delays should all be factored in.
It is strongly recommended that you let a responsible person know details of your intended route and when you expect to be back. A Route Card is one way of doing this, though as mentioned above there must be an understanding you may have to adjust your route on the day. Perhaps the most important element is to ensure you let the responsible person know you are down or at least contact them before the time you are expected back. The mobile phone revolution has greatly enhanced our ability to easily stay in contact, nevertheless their reliability is not 100%; signal coverage in remote parts of the British hills can still be patchy depending on your network provider and electronics can easily malfunction especially in a blizzard!
Top Tip: Some mobile phones allow you to use two SIM cards from different network providers, or you can carry a spare phone on a different network to improve your chances but even then there’s no guarantee of a signal.
There is no substitute or short cuts to learning navigation skills, it really is all about practice. Start off in good weather with understanding your map, learn the symbols, figure out contours and crucially know how to orientate your map without a compass. Secondly move onto the compass, learn how to take an accurate bearing from the map and to correct for magnetic variation. Practice walking on a compass bearing accurately and then learn to estimate the distance travelled over the ground on a given bearing. Don’t forget that weather conditions can add a whole new dimension.
Learning to visualise the lie of the land by inspecting the contours and other symbols on a map is the start point. Contour lines join points of equal height (usually at 10 or 15 metre vertical intervals), the closer they are together the steeper the ground. Where the ground becomes very steep contour lines often give way to the symbols for crags or rock outcrops etc. Symbols indicate the features on the ground. Line features such as streams and ridges are useful features that can be used as virtual handrails and can often help in visualising the lie of the land. Take time to become familiar with the symbols the map maker uses to show different types of terrain and features in order to plan routes and especially avoid dangerous ground. There is a wealth of information given in the margins of most maps and this is well worth studying.
Calculating speed over the ground:
When it comes to planning any route it helps to have a good idea about speed of travel to give you a general idea of how long it should take in ideal conditions and with no hiccups. To do this you need to understand the scale of the map. The most popular map scales used by walkers in the UK are 1:50,000 (2cms to 1km) and 1:25,000 (4cms to 1km). The 1:50,000 scale is ideal for a wide range of outdoor activities, but in mountainous terrain the extra detail of a 1:25,000 scale map is usually an advantage. So as a general rule of thumb we use the modern version of Naismith’s rule – allow one hour per 4 to 5km on the map (i.e. 12 – 15 minutes per km) plus 1 minute for each 10 metres of height gained. Add extra time for rest stops. Hence if your estimated speed is 4km per hour for example, then 1km with a 100 metre height gain will take about 15 + 10 = 25 minutes plus rest stops say half an hour.
This is fine when the weather is good but when the chips are down, say in appalling weather and you can hardly see your hand in front of your face, then you need to switch to micro navigation to get off the hill safely and fine skills are important. Distance estimated roughly in time is no longer accurate enough, pacing every step and staying on course by setting your compass correctly and trusting the bearing is the only way. You must be able to do this even if you have a GPS and know how to use it, electronic goods do go down, not often but they cannot be relied upon 100% (yet).
What to do when lost:
Everyone can make mistakes or perhaps become distracted, and sooner or later every hill walker is likely to become temporarily “positionally challenged.” My first advice is not to panic; these situations can be resolved safely. First stop, and then calmly and carefully examine your surroundings to see what clues are available. Note the nature of the terrain around you (if possible) and any visible features before consulting your map.
Mentally go back to the last position where you were absolutely sure of your position, and consider all the possible areas that you could now be. Challenge all assumptions and test them against the evidence. Before trying to see where you could be, see if you can eliminate places that you definitely are not, by looking at the slope angle and other features. For example, if you are on a north-easterly slope then look at the map and eliminate all positions that do not have such a slope.
Once you’ve figured out where your probable rough position is, to within a km or so then look for a suitable line feature that you can aim for e.g. stream, forest boundary etc. Set your compass to a “safe” bearing, stick to it as closely as possible eventually you should hit the line feature and then you can follow this until you come to a point you can identify. When setting your “safe bearing” make sure you avoid dangerous ground, especially in poor visibility, adjust your bearing as required to give you the best chance of finding your target safely. This technique is the ultimate fall-back measure for most lost situations though may involve a long hard walk to get back to where you want to be, better to keep a close eye all along.
Where does GPS fit in?:
Traditionally navigation has always been based around paper maps and magnetic compasses, and it’s a skill set that’s served perfectly well for centuries and continues to do so. Modern navigation aids, like GPS and digital mapping have opened up new alternatives that offer mobility, flexibility and simplicity that can help take some of the strain out of what can be a complex process. Knowing your exact location is always a good starting point for any navigation exercise, and GPS with its system of orbiting satellites can locate you to within a few metres instantly and on demand. What you do with the knowledge of where you are, and how you move on from there are areas that rely on a mix of experience and knowledge that a GPS can’t replicate completely, although they can go a long way towards it.
Traditional paper maps have long been based on data collected and stored in digital format, so it’s no surprise that in this digital age they’re easily available in computer compatible files. As pointed out in Nick Parks’ Introduction to Navigation pre-trip planning is an essential part of any navigation, and this is where digital maps and computer programs really come into their own. With programs like Anquet, Quo Pro and Memory Map you don’t just get a fixed image in 2 dimensions, but you get the ability to zoom in and out on screen, mark your projected routes non-destructively, auto-generate route cards and print out the map with your route marked on it.
Once you’ve set up your personal profile with average walking speed and made the adjustments for ascent and descent you can have the computer work out how long the walk will take whilst you get on with planning the intricate details in close-up. Every detail shown on your traditional paper map is replicated on screen, but with a computer based map you can highlight your route in a series of waymarks, where you change direction, without damaging the original map. With your route marked out the computer works out all the complex direction changes and distances to present you with a printable route card worked out to the finest detail. The only thing left to do is print your map and laminate it or print onto waterproof, tear-resistant, paper and you’ve got traditional map and compass tools but without all the mental effort of working out degrees and metres.
With modern GPS devices you can do far more than just pinpoint your location, but linked to a computer you can also transfer and record every walk you take or copy a pre-planned route straight into your GPS. At their simplest GPS receivers make an ideal backup for double checking your position, but you can also use this ability to pinpoint where you are second by second to record every step you take. Once recorded and stored the information can be transferred to a digital mapping application which can show your route as an overlay on the map and analyse the time and distance data in fine detail. File transfer works in both directions in almost all modern GPS receivers, making it easy to transfer your minutely pre-planned routes from your computer to the receiver from where you can follow the directions on the ground. On more basic models the information will simply be a series of waypoints with their grid references, allied to a direction heading and distance between each one whilst on top end models you’ll see your position in real time shown on an on-screen map identical to the paper versions.
It’s at the point where you see your position in real time marked on an on-screen OS map that people can start to use GPS as an alternative to traditional skills, and in the right hands with the right safeguards it’s a perfectly acceptable first choice navigation – but only in the right hands and with the right safeguards. It’s easy to build a sense of security with GPS, after all it knows where you are and can show you, in exactly the same way as you’d have to manually calculate, where you are on the map. One thing it will never do, however, is work out the best way to get from where you are to where you want to be. To a GPS the shortest route from A to B will always be a straight line, irrespective of lakes, rivers, cliffs or any other change in terrain, but that doesn’t make it practical to walk. Of course you have the same issue with a traditional map and compass, except that to use the map and compass you’ve built up the knowledge of exactly what the details on the map mean and how to navigate round such obstacles.
Being electronic and battery powered you have to take account of this in the same way as you wouldn’t just leave your map open on the ground in the wind; take precautions like carrying spare batteries and waterproof rugged casings where available. Modern GPS receivers don’t have the same issues with needing a line of sight to a clear sky they used to, and you can usually get a good signal even in canyons with the latest models – but you still need to be aware that signals can drop, or get distorted by high cliff walls even with the latest models. If you take care of it, and take the time to learn how to use it properly a GPS can be a great, time saving, substitute for a map and compass on a day to day basis but you have to take its fallibilities into account along with the benefits. To get the best out of a GPS you still need to know the essentials of traditional map and compass work, so why not carry the traditional tools as backup just in case?