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DESCRIPTION
Using the National Grid
1 TheNationalGridprovidesauniquereferencesystem,whichcanbeappliedtoallOrdnanceSurveymapsofGreatBritain,atallscales.
2 GreatBritainiscoveredby100kilometregridsquares,eachgridsquareisidentifiedbytwoletters,asshownindiagram A.
UsingtheNationalGrid
3 OnOrdnanceSurveymapsthesesquaresarefurtherdividedintosmallersquaresbygridlinesrepresenting10kilometrespacing,eachnumberedfrom0to9fromthesouth-westcorner,inaneasterly(lefttoright)andnortherly(upwards)direction,asshownindiagram B.
4 Usingthissystemyoucanidentifya10kilometregridsquare.Forexample,hereisTL63.Afterthelettersyouquotetheeastings(6)first,thenthenorthings(3).Ifyouhavetroubleremembering,say…
Stairs the Up Alongthehall,THEN
5 OnOSLandrangerMapsyoucanfindthetwogridlettersTLonthelegend,oronthecornerofthemap,andthegridhasbeenfurtherdividedinto1kilometreintervals,asshownindiagram C.Youcanestimatedistancesbetweenthegridlinestogiveamoreprecisereference.
6 Turnthepageandseehoweasyitistousea6-figuregridreferencetopinpointaplaceonthemap…
UsingtheNationalGridcontinued
The6-figuregridreference
7 The6-figuregridreferenceisveryusefultolocateaparticularplaceonamap.
8 Byestimatingtheeastingsandnorthingstoonetenthofthegridinterval,youcanspecifyafull6-figuregridreference,accuratetowithin100metresontheground.
9 Allyoudoisestimatehowmanytenthsawayfromthegridyourpointfalls.Forinstance,thepointindiagram Dis3tenthseastofgrid62and7tenthsnorthofgrid31.
10Onceagain,readingfromthesouth-westcorner,quotealltheeastingsfirst,thenthenorthings.The100-metregridreferenceofthepointinthediagramisshownlikethis:TL623317.
11Hereisanextractfroma1:50000scalemap.UsetheNationalGridreferencesystemtofind:
The Church at TL683365 The Windmill at TL726350 Mill Farm at TL701352
General enquiries: +44 (0)8456 05 05 05Textphone: +44 (0)23 8079 2906 (Deaf and hard of hearing users only please)
Published by Ordnance Survey, Romsey Road, SOUTHAMPTON, SO16 4GU.Ordnance Survey, the OS Symbol, OS and Landranger are registered trademarks of Ordnance Survey, the national mapping agency of Great Britain.