The SD5821 Square Kilometre

SD5821 National Grid Square

Based in the North West English Region.

The SD5821 square kilometre intersects with the settlement of Whittle-le-Woods.

SD5821 is within the post town of Chorley, Lancashire.

The square is within Chorley District council.

The Point of Origin (0,0) is 552.63 Kilometres away. This is where the National Grid starts around 80 kilometres west of the Isles of Scilly.

Ordnance Survey Maps for SD5821

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Map Series	link	Ordnance Survey
Explorer 1:25,000 285 Southport and Chorley	Shop for this map on amazon.co.uk	Buy Direct from the Ordnance Survey
Explorer 1:25,000 286 Blackpool and Preston	Shop for this map on amazon.co.uk	Buy Direct from the Ordnance Survey
Landranger 1:50,000 102 Preston & Blackpool	Shop for this map on amazon.co.uk	Buy Direct from the Ordnance Survey

This extract is taken from the Ordnance Survey six-inch to the mile series surveyed from 1888-1913. The scale is 1:10,560.

The Square overlayed over the map represents the extent of SD5821 and the vertical and horizontal line divides the square into four quadrants

Dividing the SD5821 Square to get a six figure Grid Reference

A helpful reminder for calculating grid references is across the landing and up the stairs.

For example if your house was located in a square that in the fourth square across and sixth square up and you wanted to work out its six figure grid refence.

First, You would divide the four figure grid reference into three parts. SD , 58 and 21

Count across starting with zero. This would give you three. Make a note that X for Across (A Cross) = 3.

Count up starting with zero. This would give you five. Make a note that Y = 5.

So to put it together SD + 58 + 3 + 21 + 5 would give you the six figure grid reference of SD583215

SD	58		21
SD	58	3	21	5

A six figure grid reference would be accurate to 10 metres. To achieve a greater level of accuracy this 10 metre square would be divided into a grid 10 by 10 and the process repeated.

This would produce an 8 figure grid reference that would be accurate to a square metre!

Corner	Latitude	Longitude	Easting	Northing
South West Corner	53.683774	-2.637521	358000	421000
South East Corner	53.683774	-2.622246	359000	421000
North West Corner	53.692841	-2.637521	358000	422000
North East Corner	53.692841	-2.622246	359000	422000