The Ordnance Survey National Grid reference system (OSGB), also known as British National Grid (BNG), is a system of geographic grid references, distinct...

The Ordnance Survey (OS) is the national mapping agency for Great Britain. The agency's name indicates its original military purpose (see ordnance and...

Ordnance Survey Ireland (OSI; Irish: Suirbhéireacht Ordanáis Éireann) was the national mapping agency of the Republic of Ireland. It was established on...

−200 m is used; thus a depth of −60 m is 140 m ATD Ordnance Survey National Grid – System of geographic grid references used in Great Britain Principal Triangulation...

mapping Ordnance Survey National Grid, used in Great Britain Irish national grid reference system United States National Grid National Grid for Learning...

of the British National Grid was released in 1938, based on earlier experiments during World War I by the Army and the Ordnance Survey. During World War...

datum and Ordnance Survey National Grid in use today. The retriangulation was begun in 1935 by the Director General of the Ordnance Survey, Major-General...

and no smaller than 5x5 minutes of latitude and longitude. Ordnance Survey National Grid is another Transverse Mercator system designed for locations...

Grid reference Ordnance Survey National Grid (British National Grid) Irish national grid reference system Spatial Reference System List of National Coordinate...

the Cassini Grid system was replaced with the Ordnance Survey National Grid (see § Transition to National Grid). However, the Cassini Grid system continued...