How to read maps

Maps have a grid laid over them that is numbered so that it makes it easier to find things. The grid lines and numbers are in light blue. The numbers are called grid references. You can have 4, 6, 8 and 10 figure grid references.


Please contact the County Archaeological Service for the three maps to accompany this worksheet.


Look at the map of north Buckinghamshire your teacher gives you. You can see Leighton Buzzard to the east and Winslow to the west. Milton Keynes is north of the map and Aylesbury is south of it.


You always read the grid reference heading east first and then the reference heading north. Where the 80 line crosses the 20 line just south of Whitchurch is grid reference 8020. Because there are not enough numbers to cover the whole of England, the grid reference also uses letters. In this area all the grid references start with SP, so here the grid reference is SP8020. This grid reference also refers to everything in the box to the east and north of this crossing point. So Cublington, Stewkley and Ascott House are all in SP8020. What other villages are in SP8020?


What is the grid reference where the 90 line crosses the 30 line just south of Great Brickhill? What is the grid reference of the box Great Brickhill is in?


What is the grid reference where the 90 line crosses the 20 line? Which town is in this box? 


In the next map your teacher gives you we have zoomed closer in to Whitchurch. The big SP8020 box in the above map has been divided into smaller boxes. We can still make four-figure grid references here. For instance, the north-west end of Creslow is almost exactly at SP8122.


What is the grid reference at the north end of Whitchurch? Again the grid reference also refers to the box to the east and north of the crossing point. So Hartwell Farm, for instance, is in box SP8123. Which farms are in box SP8320?


We can also start doing 6-figure grid references. You have to imagine that each box can be divided into smaller boxes by ten vertical and ten horizontal lines. Beechmoor Farm is just to the east of the 81 line and about half-way between the 20 and 21 lines. So Beechmoor Farm is at about SP811205. Hurdlesgrove is almost halfway between the 80 and 81 lines and very close to the 23 line, so it is at about SP804228.


Give a 6-figure grid-reference for the Motte (a castle) and village earthworks in the north-east of the map. Give a 6-figure grid reference for Hartwell Hill Farm. 


In the third map your teacher gives you we have zoomed in again to Whitchurch. You can still see lines 80 and 81, 20 and 21. You can still do a 4-figure grid reference. SP8021 is just about where the smaller yellow shaded roads come off the main red road in the north-west of the map.


We can also do 6 figure grid references, but now more accurately. Measure the distance between 80 and 81 and divide it by 10. Draw horizontal and vertical lines in box SP8020 to divide it into 100 smaller boxes. The post-office (where it is marked PO) should be at 6-figure grid reference SP802206. It can’t be at SP8226 because that would make it a long way to the north-east. The east end of the village is at SP808203. Give a 6-figure grid reference for the pub (centre on the blue beer mug).


But what you will find is that they are not exactly at the point where the lines you have drawn cross. The post-office is actually within the box to the north-east of SP802206. To get a more accurate position, you can do 8-figure grid references. This would make the post-office at SP80252060, because it is half-way between 802 and 803, but should be right on the 206 line. The east end of the village is actually at SP80832036.


Try to do an 8 figure grid reference for the church (the black square with a cross on top). Give the 8-figure grid reference for the large pond north of the east end of the village.


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