A grid reference is a standardised way of describing a precise location on a map. They are used by emergency services, national parks, and search and rescue teams to communicate locations accurately. Knowing how to read and give a grid reference is a practical skill for anyone who goes into remote terrain regularly.
How the Grid Works
Australian topographic maps use the Map Grid of Australia, which divides the country into 1km grid squares. Each square is identified by a zone, an easting, and a northing. The easting runs east-west across the map. The northing runs north-south. Together they identify a specific square or, with additional digits, a more precise location within that square.
Reading a Six-Figure Reference
A six-figure reference identifies a location to within 100 metres. The first three digits are the easting, read left to right across the map. The second three are the northing, read bottom to top. To estimate within the kilometre square, estimate where in the square your location sits and add a digit to each. This is easier in practice than it sounds written out.
Getting Your Reference From a Phone
Most mapping apps show your grid reference in the location information. In Gaia GPS, tap your position and the coordinate is displayed. In Avenza Maps, the same. If you are ever in an emergency situation and need to give your location to emergency services, know how to find this information before you need it, not while you are on the phone trying to work it out.
Giving a Reference Over the Phone
When giving a grid reference to emergency services, give the map zone first, then the easting and northing clearly. Read it slowly and confirm it back. A wrong digit in a grid reference puts a search team in the wrong place. Zone 55 H, easting 312, northing 458 is clearer than a stream of numbers without structure.
