The SK9991 Square Kilometre

SK9991 National Grid Square

Based in the East Midlands English Region.

The SK9991 square kilometre intersects with the settlement of Glentham.

SK9991 is within the post town of Market Rasen, Lincolnshire.

The square is within West Lindsey District council.

The Point of Origin (0,0) is 633.94 Kilometres away. This is where the National Grid starts around 80 kilometres west of the Isles of Scilly.

Ordnance Survey Maps for SK9991

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Map Series	link	Ordnance Survey
Explorer 1:25,000 281 Ancholme Valley	Shop for this map on amazon.co.uk	Buy Direct from the Ordnance Survey
Landranger 1:50,000 112 Scunthorpe	Shop for this map on amazon.co.uk

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 SK9991 and the vertical and horizontal line divides the square into four quadrants

Dividing the SK9991 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. SK , 99 and 91

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 SK + 99 + 3 + 91 + 5 would give you the six figure grid reference of SK993915

SK	99		91
SK	99	3	91	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	53.406376	-0.512255	499000	391000
South East Corner	53.406376	-0.496902	500000	391000
North West Corner	53.415550	-0.512255	499000	392000
North East Corner	53.415550	-0.496902	500000	392000