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Four-Figure Grid References

Pinpoint one-kilometre squares using eastings first, then northings.

  • Define and explain Four-Figure Grid References in your own words
  • Use key terms such as eastings accurately
  • Apply what you have learned to new examples and questions
  • Avoid the common mistakes learners make with this topic

This lesson focuses on Four-Figure Grid References: pinpoint one-kilometre squares using eastings first, then northings.

Definition: Four-Figure Grid References

Pinpoint one-kilometre squares using eastings first, then northings.

Key ideas

Along the corridor, then up the stairs

Grid references always give eastings first, then northings. Imagine walking along a corridor (across the map) before climbing stairs (up the map). A four-figure reference like 4738 names the 1 km square whose south-west corner is at easting 47 and northing 38.

Six figures give 100-metre precision

To be more precise, divide the 1 km square into tenths. The extra digits estimate how far across and up the square the feature lies — a six-figure reference pinpoints a 100 m by 100 m square. Estimate the third and sixth digits carefully; they are the ones most people get wrong.

Key term — eastings: The vertical grid lines on a map, numbered from west to east — read these first in a grid reference.

Worked example: Four-Figure Grid References

What area does a four-figure grid reference identify?

A 1 km by 1 km square.

Answer: A 1 km by 1 km square.

Common mistakes
  • Writing a four-figure reference when six are needed Four figures only name the whole 1 km square. If the question asks for a specific building, you need the extra precision of six figures.
  • Giving northings before eastings It must be eastings first — 'along the corridor, then up the stairs'. Reversing them points to a completely different square.

Practice

In a grid reference, do eastings or northings come first?
Think: along the corridor, then…

Eastings come first, then northings.

How precise is a six-figure grid reference?
Each square is split into tenths.

It identifies a 100 m by 100 m square.

On a 1:50,000 map, two villages are 6 cm apart. How far apart are they in real life?
First work out what 1 cm represents.

1 cm = 500 m, so 6 cm = 3 km.

On a 1:25,000 map, what real distance does 8 cm represent?
On this scale 1 cm = 250 m.

8 × 250 m = 2,000 m, which is 2 km.

Quick check

Four-Figure Grid References — quick check

Which of these best defines "eastings"?

The vertical grid lines on a map, numbered from west to east — read these first in a grid reference.

Contours on a map are packed very closely together. What does this tell you about the slope?

The slope is steep.
Key takeaways
  • Four-Figure Grid References: pinpoint one-kilometre squares using eastings first, then northings.
  • Along the corridor, then up the stairs: Grid references always give eastings first, then northings.
  • northings: The horizontal grid lines on a map, numbered from south to north — read these second.
  • Watch out for: writing a four-figure reference when six are needed
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