WWI Marginal Information: Corner Coordinates

The state of coordinate and grid systems at the beginning of the war was chaotic to say the least. Many of the only maps available were old and of various national origins. At one time each nation, except England, used its own capital city as the point through which to run the prime meridian or "zero" line of longitude. England chose the site of its Royal Observatory in Greenwich. When examining the maps from this time period one must determine whether or not the degrees are West or East of Paris, Brussels or Greenwich.

The British soon dropped the latitude and longitude system based on degrees in favour of a military grid of 1,000 yard squares to aid its artillery in ranging and to make map referencing easier. This, however, was eventually changed to a grid of 1,000 metre squares in order to properly fit the French and Belgian base maps which were in metric units.