Topographic map
A topographic map is a detailed graphical representation of the ground in an orienteering competition. The scale of an orienteering map can be 1:15.000 or 1:10.00, each object and particular shape of the land is represented with a symbol. Colours have specific meanings as well: white indicates a crossable forest; green, from light to dark, represents increasingly dense vegetation; yellow symbolizes the open land (meadows and glades); brown indicates the land, whereas blue indicates water; black marks roads, trails, paths, houses, artefacts such as light poles, etc.
Even contour lines (or isohypses) are indicated. They are closed curves that unite all points of the same altitude with respect to the sea level, which it is considered level zero. In addition to these symbols, in order to read the map it is necessary to use the legend, that is the list of symbols used in the map followed by their meaning. In order to orient the map correctly, it is necessary to use a compass lining up the North on the map with that indicated by the compass. In order to do so, you should put the compass on the map keeping both parallel to the ground; then, you need to rotate them as a single unit until the direction of the magnetic needle will be parallel to the North of the map. The map can be read in two main ways.
- Thumbing the map: it means that you grip the map with your thumb just below the exact spot where you are. In orienteering it is fundamental to maintain contact with the map, always knowing exactly where you are. Moving your thumb along the map as you move through the terrain helps you keep this contact.
- Overall reading: in this case, it is not necessary to locate your position step by step, as it is easier to choose a number of objects clearly recognizable on the ground and to rely on them to stay on the correct path.
