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Geolens

Glossary

417 words used in the labs.

Find a term from the labs, understand the process behind it, and see how it appears in the landscape. Each entry connects an explanation with a real observation and a model you can explore.

Term

Four-figure grid reference

A reference identifying a 1 km square on a standard British National Grid map by its southwest corner. Read the easting first and then the northing. It identifies a square, not an exact point within it.

What to look for

Ordnance Survey sheet NO, northeast Scotland. British National Grid eastings and northings are measured from a false origin southwest of Great Britain. Four figures identify a 1 km square; six identify a 100 m square. This reduced 1:250,000 sheet illustrates the system; use a detailed map for precise references.

Related labs

Grid references →
Ordnance Survey 1:250,000 map sheet NO of northeast Scotland with the British National Grid.
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