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What datum and projection is used? If you are going to use the coordinates

from the map, you will need to determine which coordinate system (or datum) and
projection is used on the map.
Always include a reference to the datum or projection when quoting
coordinates. Datums and projections are explained earlier in this booklet. This
information will be contained in the text on the map footer (see previous section

‘Datum and projection information panel’).
If you’re using a Global Navigation Satellite System (GNSS) such as the
Global Positioning System (GPS), remember to set your GNSS receiver to the

same coordinate system as your map, or a compatible one.
To explain scales graphically, look at a 1:25 000 scale map. The first number
of the scale (1) represents a core unit of distance on the map, while the second
(25 000) represents that same distance on the ground.

In this case, one centimetre on the map represents 25 000 centimetres, or 250
metres, on the ground.
Example: The measured distance between two points on the map is 9 cm at
the map scale 1: 25 000. What is the distance between those points on the ground?

D  9 cm 250 m  2250 m
DISTANCE
In addition to the map scale, most maps also show a scale bar:

Fig. 1.3 Scale bar on topographic maps

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