Basic map and compass skills are often overlooked by paddlers but are essential if you’re hunting down the next stout or need to walk out from a river. Global Positioning Satellite (GPS) technology has changed many aspects of navigation. This doesn’t negate the need for a basic understanding of map/compass use. Batteries don’t last forever and you just know that if you’re in a tight spot your GPS is bound to breakdown! However that said if you need to pin point your position in bad weather (or otherwise) a GPS will do it damn quick.
Maps are essentially a 2D representation of a 3D world. Maps contain a huge range of information that can on first glance look very intimidating. But given some time and very little effort you can unlock that information and begin to use maps to your advantage.
Quite often the best way of learning to map read is to study maps. Get a map and try and trace routes that you have done in the past. Try and identify features. Use the maps key to work out what each symbol means. Every symbol and feature you can identify will be an advantage when you’re out in the hills or on the water and need to use a map.
A ratio or representative fraction (RF) indicates how many units on the earth’s surface is equal to one unit on the map. For example 1:50000 where 1 cm on the map represents 50000 cm’s on the ground.
This ratio of scale can also be given as a word statement. This gives a written description of scale, such as “Two centimetres equals one kilometre”, which is the case on a 1:50000 scale map.
Contours are lines on a map that link places of equal height. On OS 1:50000 and 1:25000 maps the contours are spaced at 10 metre intervals. To aid counting thicker contour lines are placed every 50 metres. You’ll also find that some of the contour lines will be labeled with their height above sea level (in metres).
The closer the contours are together, then the steeper the terrain will be.
This is the key to map reading success. You must be able to look at a map and the visualize what it looks like on ground. This takes practice. The best way to do this is to get a map of a place you are familiar with, you will find it much easier to relate what you are familiar with, with the detail on the map. After practice you should be able to reverse the process and be able to visualize real life from the detail given on any map.
All of the new electronic mapping software, like Memory-Map, Tracklogs and Anquet allow you to see the map in 3D or even see a satellite image transformed into 3D. This often aids the learning process, but nothing can beat being out on the ground map reading for real.
Features you NEED to know