100 words - day 13

The British National Grid and Ordnance Survey

Given that I’m currently based in the UK, my go-to map projection is the British National Grid (BNG) which also happens to be used on all Ordnance Survey (OS) maps in the UK.

Essentially the UK is split up into a grid system which starts in the very South Western part of the UK (just to the south and west of the Isles of Scilly) and there are vertical lines (eastings), that increase in value as you move eastwards and horizontal lines (northings), that increase in value as you head north up the map. This forms a grid square is denoted by two letters which forms the National Grid System. These grid squares are 100km across and are further subdivided into smaller squares 10km intervals and on some maps this is subdivided further to 1km intervals.

This brings us to the six figure grid reference we get taught in school and when navigating on your Duke of Edinburgh expeditions and helps locate features within a specific area.

This map projection works really well when the area of interest is focused on the UK, but would be pretty useless if you were in Australia or Asia!

British National Grid