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Grid references
on OS maps
How to give
four figure grid
references
You might have done this in Maths.
• What is this?
X
A cross
Across
Stand up
Cross your arms, move side to side and say,
“X IS ACROSS”.
Touch your toes then reach up and say,
“Y TO THE SKY”.
• Complete the sequence…..
A, B, C, D, …………….
• w, X, Y, z
• So x coordinate comes before the y
coordinate.
20
y
19
18
17
16
15
14
13
12
11
10
The coordinates are
9
8
(12,16).
7
6
5
4
3
2
1
x
0
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20
20
y
19
18
17
16
15
14
13
12
11
10
The coordinates are
9
8
(12.5,16.2).
7
6
5
4
3
2
1
x
0
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20
A grid reference is a
way of giving a position
on a map
Grid line
numbers
are at the
top and
bottom
31
32
33
34
35
36
So this is
Easting 35
Grid lines
called
Eastings
are from
top to
bottom
Say it as ‘three
five’, not as
thirty five.
31
32
33
34
35
36
Grid lines from side to
side are called Northings
27
Grid line numbers are
along both sides
27
26
26
25
25
24
24
23
22
So this is
Northing 24
Say it as ‘two
four’, not
twenty four
23
22
31
32
33
34
35
36
27
27
26
26
A
25
25
What is the four
figure grid reference
for this square?
24
23
24
23
22
22
31
32
33
34
35
36
31
32
33
34
Find the
line along
the left of
the square.
35
36
35
36
A
This is
Easting 34
31
32
33
34
Find the line along the
bottom of the square.
This is 27
Northing 25
26
27
26
A
25
25
24
24
23
23
22
22
The four figure
grid reference
is 3425
34
Easting 34
A
25
Say it as
‘three four
two five’
Northing 25
20
y
The four figure grid
19
18
reference is 1216
17
16
15
14
13
12
The
coordinates are
11
(12,16).
10
9
8
The coordinates give
the point and the grid
reference gives the
square.
7
6
5
4
3
2
1
x
0
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20
Remember
•
•
•
•
•
•
Find the square
Look at the line on its left (Easting)
Find its number from the top or bottom
Look at the line along its bottom (Northing)
Find its number from either side
Write the Easting number, then the Northing
number
What are the
four figure
grid
references for
the squares
with these
symbols?
3124
31
32
33
34
35
36
27
27
26
26
25
25
24
24
23
23
22
22
3223
3525
3522
3325
All right?
Some wrong?
Double click icons
31
32
33
34
35
36
How to give a
six figure grid
reference
31
32
26
33 church
34 is in
35
36
The
27
square 3224, but
where exactly is it?
26
25
25
24
24
23
23
22
22
27
31
32
33
34
35
36
31
32
33
34
35
36
27
27
26
26
It is nearer to
33 than to 32
25
25
But how
‘near’ is
nearer? 24
We need to
look more
closely. 23
24
It is nearer to
24 than to 25
23
22
22
31
32
33
34
35
36
Look
closer at
one grid
square
328
320
330
250
25
Draw
lines
between
the main
grid lines
A six
figure
reference
at
328243
243
240
32
Say it as
‘three two
eight, two
four three’
24
33
20
The 6 figure grid
y
reference is 125162.
19
18
17
16
15
14
13
12
11
10
9
8
The coordinates are
7
6
(12.5,16.2).
5
4
3
2
1
x
0
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15 16 17 18 19 20
Remember
• Find the point in the square
• Find the four figure grid reference
• See how far the point is from the line on the
left of the square to the line on the right
• See how far the point is from the line along
the bottom of the square to the line along
the top
Where are
these
symbols?
320
330
250
250
240
240
325243
326247
327240
330248
322246
All right?
Some wrong?
Double click icons
320
330
32
Remembe
r
This line first
3224
24
Then this line
Remember
32
327
This line first
246
Then this
line
24
Church at 327246