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Grid systems divide the curved surface of the earth into a two-dimensional referencing system.
Both systems covering Great Britain and Northern Ireland use a metric scale.
The diagrams below show the alignments with a 100 km interval.
Grid systems divide the curved surface of the earth into a two-dimensional referencing system.
Both systems covering Great Britain and Northern Ireland use a metric scale.
The diagrams below show the alignments with a 100 km interval.