Maps that show the height of the land and other features, like rivers, are called physical or relief maps. Map-makers use colours and lines to show the height of the land and how steeply it rises and falls. Heights and depths on a map are measures above and below the average level of the sea.
Colours for height
These drawings show how the hills and valleys that we see in the countryside can be simplified into flat maps. First, an area is divided into sections or bands of different heights. All land areas of the same height are given one colour. The lowest land is usually coloured yellow or green and higher land is shown in different shades of brown. On the flat map below, it is easy to see which areas of land are higher. For example, the highest land is shown in dark brown. Another way that we can show height on a map is by using contour lines. What are contour lines? Imaginary lines called contour lines are an important way of showing the rise and fall of the land on a map. Contour lines show all the places that are the same height above sea level. Contours also tell us about the slope of the land. On a steep slope, the lines are closer together. On a more gentle slope, they are farther apart. If there are no contour lines, the land is almost flat.
High Hills, Flat Maps
Here you can see how the two hills shown on the right have been mapped using contour lines. Again, the land has been divided into coloured bands according to height, but his time each band has been given a height in metres.
Steps to be taken
1. Outside, build a hill out of damp sand on a wooden board. 2. Push a pencil or stick into the sand to make several rows of holes all the way around the hill. The holes in each row should be at the same height. Use a ruler to help you keep the holes level. 3. Wrap lengths of string around the hill to join up the holes in each row. 4. Look down on your hill. The lines of string will look like the contour lines on a map. See if you can draw the lines on a flat map.