Navigation is difficult isn’t it? Once you know how it’s done it’s logical, the key is lots of practice and actually bothering to practice so the information doesn’t just march right back out of your brain will definately help you. We are by nature as a species a bit lazy so if we think it’s not necessary to do something, then we won’t. Such an economical attitude with navigation can end up with mistakes that take longer to resolve than making the extra effort in the first place.
For a map to work, it requires three elements to be taken into account and an ability to identify and use each effectively. You need to be able to define direction, you need to be able to measure distance and you need to recognise symbols to represent the landscape around you.
DIRECTION || To give direction, you need a fixed reference point and on maps that is always north. All OS maps have a grid, which is made up of vertical grid lines that run north-south and horizontal grid lines that run east-west. North is at the top of the map and most text is aligned to be read with north at the top. The importance of map orientation cannot be over-emphasised. Whichever method you use, it should be the first thing you do every time you look at the map. Get to know your northings and eastings and how to read and use these in your calculations.
DISTANCE || To measure a distance off a map you need to know the scale of the map. The most commonly used scales in the UK for mountain bikes are 1:50,000 and 1:25,000.
A scale of 1:50,000 simply means that 1 unit on the map represents 50,000 units on the ground. Most people find it easier to think of how many cm to the km. And as the navigation becomes more complex it is useful to think how many mm on the map represents 100m on the ground.
1:50,000 = 2cm to the km, 2mm = 100m and 1:25,000 = 4cm to the km, 4mm = 100m
The edge of most compasses should have a ruler graduated in mm. This enables you to measure distance off the map and convert it to distance on the ground.
SYMBOLS || Find some time to open out your map fully and look at all the information in the legend and around the border of the map. As well as a full legend to the symbols used on the map. Get to know all your symbols and keys so you know exactly what you are likely to encounter in reality. Familiarise yourself with contours – this is simply a line of equal height. The height difference between successive contours is called the contour interval. OS maps have a 10m interval. Every 5th contour is thicker to make it stand out on the map and these are called index contours. Understanding contours and being able to see a clear 3D image of the ground represented by the 2D pattern of the contours is a really helpful skill. Just think “The Matrix”.
To be able to navigate with map and compass you will need to get some experience. Go to a familiar area and get used to orienting your map correctly, use your compass to check you have oriented the map correctly. Identify the landscape features around you and track them back to the map symbols and markings, think about the terrain and tie it back to the contours and the landscape features around you get to grips with measuring and accurately measuring distances. Having an estimation of the distance travelled to add to your mental description of your journey helps increase the accuracy of your positioning for your new location.
A really great resource to further understand and practice reading maps is provided free of charge from Ordnance Survey in this handy Downloadable PDF – Map Reading from Easy to Advanced. No excuses, get out and practice your navigation!