A map is a two-dimensional representation of all or part of the spherical globe. Here we will concentrate on the information needed to read one correctly.
First off, there is the scale, which may be represented in two ways, either numerically or graphically. In the first case, the numbers indicate the relationship between the actual distance and the distance on paper. If there is a scale on a map of, for example, 1:10,000, it means that 1 centimetre on the map corresponds to 10,000 centimetres, or 10 metres, of terrain. If you look at various different maps, you will see that the first number is always 1 and that the second can differ. The larger it is, the larger the surface of the globe represented and, consequently, the less precise it is.
A graphic scale has the same function but uses a line with divisions which represents real measurements in metres (normally corresponding to the second number on a numerical scale) and which serves as an example to use for taking measurements on the map.
Another important feature of a map is the contour lines, which are a way of representing elevations of the land on paper. They are imaginary lines which unite points situated at the same elevation above sea level. The succession of lines and the use of different colour shading enable you to form a mental representation of the contours of the land.
The contour lines always have equidistant elevations between them and they vary according to the scale of the map. Every x number of metres you will find a master contour which indicates the elevation of that line. In between the lines you have to add or subtract the space between them from the value of the master contour in order to find the exact elevation.
In order to orient the map the first thing to remember is that the top of the map always represents north. With this in mind, you then locate two or three easily recognisable landmarks (a house, mountain peak, river, etc.) and identify them on the map. If you align these points with their representations on the map you will know where north is and be able to interpret the rest of the map so as to decide which direction to take.