GRID REFERENCES MADE EASY

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GRID REFERENCES MADE EASY. GRID REFERENCES MADE EASY. A GRID REFERENCE is a number which gives a location on a map They are very useful in Scouts when we’re out hiking We can use them to find out where we’re supposed to be… ...or if we get lost we can tell someone where we are!. - PowerPoint PPT Presentation

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www.9thHuddersfieldScouts.orwww.9thHuddersfieldScouts.org.ukg.uk

www.9thHuddersfieldScouts.orwww.9thHuddersfieldScouts.org.ukg.uk

GRID REFERENCESGRID REFERENCESMADE EASYMADE EASY

www.9thHuddersfieldScouts.org.uk

GRID REFERENCES MADE EASY

A GRID REFERENCE is a number which gives a location on a map

They are very useful in Scouts when we’re out hiking

We can use them to find out where we’re supposed to be…

...or if we get lost we can tell someone where we are!

www.9thHuddersfieldScouts.org.uk

The grid references we usually use are SIX FIGURE references

They will look something like this:

216409A bit like a phone number!

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These numbers refer to the GRID which covers all maps

Here they’re marked in PINK so you can see them, but they’re usually BLUE

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The grid is labelled with GRID NUMBERS at the bottom and left sides of the map

20 21 22 2340

41

42

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21 22 23

The numbers at the bottom are called NORTHINGS because the label grid lines which go NORTH

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The numbers at the bottom are called EASTINGS because the label grid lines which go EAST

40

41

42

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21

Each Northing refers to the column to the right of it’s grid line

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Each Easting refers to the row above it’s grid line

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Where are these NORTHINGS and EASTINGS in the Grid Reference?

21640921 40NORTHING EASTING

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Both numbers combined give a square on the map...

21

The grid reference of this square is 21 40

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How do you remember WHICH COMES FIRST though?

Well, just remember

NORTHINGS FIRSTNORTHINGS FIRST…and that NORTHINGS are the numbers along the bottom, labelling the lines that go NORTH!

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GRID REFERENCESMADE EASY

EXERCISE ONEFIND THE SQUARE

You’ll have a map between two, and a list of 6 figure grid references - just find the big square for each one

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OK so we now know how to find the square from these numbers:

21640921 40But what about these ones?

6 9

What are they for?

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Well the 40 and 21 only give you a big square one kilometre wide!

4021

Not much use if you need to know where to go exactly!

1km

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So we split each square into 100 smaller squares...

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Each square is labelled like the grid before, but with just one number from 0 to 9

0 1 2 3 4 5 6 7 8 9

9876543210

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So, same as before, a square is identified by a NORTHING and an EASTINGRemember, NORTHING first

0 1 2 3 4 5 6 7 8 9

9876543210

So what’s the two numbers which identify this square?

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That’s right: 4 and then 7

4 first as it’s the NORTHING

0 1 2 3 4 5 6 7 8 9

9876543210

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Then 7 as it’s the EASTING

0 1 2 3 4 5 6 7 8 9

9876543210

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OK, let’s put it all together… See the spot height marked 375 in the square below?

20 21 22 2340

41

42

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Let’s find out it’s full 6 figure reference

_ _ _ _ _ _First, what square is it in?

20 21 22 2340

41

42

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20 21 22 2340

41

42Yes, 21 - 40!But where does this fit into the 6 figure reference?

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20 21 22 2340

41

42

2 1 _ _ _ _21 first

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20 21 22 2340

41

42

2 1 _ 4 0 _Then 40

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20 21 22 2340

41

42

Both together... 2 1 _ 4 0 _

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20 21 22 2340

41

42 Now we need to look at the missing two figures:

2 1 _ 4 0 _

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20 21 22 2340

41

422 1 _ 4 0 _So we add the grid - usually you do this in your mind!

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20 21 22 2340

41

422 1 _ 4 0 _The spot height is in this square

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Zooming in...

0 1 2 3 4 5 6 7 8 9

9

8

7

6

5

4

3

2

1

0

2 1 _ 4 0 _22

2

2

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20 21 22 2340

41

42 So now we have the full grid reference:

2 1 2 4 0 2

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20 21 22 2340

41

42

OK, what about the station in Llangollen?

_ _ _ _ _ _

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20 21 22 2340

41

42

OK, what about the station in Llangollen?

214422

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20 21 22 2340

41

42

OK, where’s this one...

204408

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20 21 22 2340

41

42

OK, where’s this one...

204408 Answer: Bank Fm

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GRID REFERENCESGRID REFERENCESMADE EASYMADE EASY

EXERCISE TWOPRACTISE MAKES PERFECT

You’ll have a map between two, challenge each other to give the grid ref for a place, and the places for given refs