Title: How to Use Map Scales and Grids
Headings: How to Use Map Scales and Grids
How to Use Map Scales and Grids
Understanding map scales and grids is key to making full use of your map
Map Scales
Map Grids
Discovery Series Map Grid
Four-figure grid references
Watch the 3 other videos in this set.

Content: A Discovery series map will also give you centre of sheet coordinates in Irish Transverse Mercator (ITM) which is a newly derived GPS compatible mapping projection that is associated with the European Terrestrial Reference System 1989 (ETRS89). Four-figure grid references
As we already said, when giving a four-figure grid reference, always give the eastings number first and the northings number second. An easy way to remember this is to keep in mind the letters HV ( H igh V oltage), that is horizontal reading first followed the vertical reading. In the diagram below, the number 4 is in square 28 across (on the horizontal) and square 54 up (on the vertical) and therefore, the four-figure grid reference is ‘2854’. The other numbers in the squares above would get the following grid reference. 2755
2855
2754
2854
In order to be a little more precise with your grid references, you can give a 6 figure grid reference as shown below. In the above diagram, we have taken the lower right square from the previous diagram and divided it by 10 in each direction. The pink circle is in the four-figure grid reference square ‘2552, but more accurately it is 2 tenths across and 7 tenths up within that enlarged grid square, therefore the six-figure map reference is ‘252527’. The red circle has a 6 figure grid reference of 257522. Ireland is covered by the National Grid, that is the country is divided into 25 squares from A to Z (the letter i is not used).