What Are Grid References?

Basic Grid References

• The most basic grid reference system is likely seen on a standard road map. Square grid lines are drawn across a map, with numbers increasing horizontally and vertically away from the bottom-left corner, each number next to a single square. This corner is referred to as the "origin", the numbers on the horizontal axis running west to east are "Eastings" and the numbers on the vertical axis running south to north away from the origin are called "Northings". In this way, the square in the bottom left corner would have the reference 11, as it is positioned between Easting 1 and Northing 2. Moving to the east, the next square would be 21, and then 31. If you then moved north, you would be on square 32. Most road maps will use miles or kilometres as their scale, and may use letters rather than numbers for the Northings.

Specific Points

• The more numbers are added to a grid reference system the more specific a location can be pinpointed. Adding a further two digits to any grid reference does this. These additional digits refer to an imaginary ten-by-ten grid within the referenced square. For example, if you were looking for 2311, you would be looking for the bottom left corner of grid reference 23. 2399 would be the top right corner. According to the Country Walkers website, the standard for grid references is six-digits.

GPS

• As technology has advanced, Global Positioning Satellites can now tell us our location anywhere in the world using GPS handsets. These will usually deliver a ten-digit grid reference, so already this is far more specific than anything so far. Each additional two digits pinpoint the location by a factor of 10. Ultimately this means that you can pinpoint your location to exactly where you are standing.

Applications

• Grid references are used in all manner of situations, be it for a hobby or work. You may need to use them if you are out driving and need to consult a road map, or if you take up orienteering or hill walking. When a town is being planned, surveys will be taken with points of interest recorded as grid references. Archaeologists use grid references to make sure they can return to an important find, while the armed forces use grid references to draw up plans, move across the environment and select targets for attack. Even a child's treasure hunt can use a basic grid reference system.