These systems have largely disappeared from modern map making, but they are intriguing to read about. Prior to this, various systems of drawing the relief had been experimented with, including a system called hachuring. Please refer to the Further Reading hyperlinks to learn more about contours and understanding what they mean.Ī bit of history: Contours were developed in the 19th century (1800s). The reading of topographic maps and interpretation of contour lines, is a much written about topic. As a result of this selection process, the difference in density of the contour lines is only indicating relative changes in the shape of the landscape – on that map! This is called the contour interval of the map. For example every 20, 50, 200 metres – depending on the scale of the map.
On the Nullarbor Plain, for instance, very few contour lines would be shown, but over the Snowy Mountains an enormous number of contour lines would be shown.Ī word of warning: topographic maps do not show every contour line, rather they choose sample of the lines. The closer contours are together the steeper the land and the further they are away from each other the flatter the land. Where these lines are above sea level they are simply called contour lines and where they are below sea level they are called bathymetric contour lines.Ĭontour lines can tell an informed reader many things about the shape of the land and its ruggedness. In simplistic terms a contour line is a line which joins points of equal elevation. This map had a contour interval of 20 metres.Įlevation is usually shown using contour lines. This extract from a 1:50,000 scale map has been annotated in pink to highlight different landscape features which can be identified using the contour lines.
TOPOGRAPHIC ELEVATION MAP SERIES
Topographic maps are usually part of a series of maps, but may be one–off / stand–alone maps.
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