The slides explain contour lines on maps, which represent the relief or shape of the land by connecting points of equal height above sea level. Contour lines are numbered to indicate elevation, with closer lines indicating steeper slopes and fewer lines suggesting flatter terrain. The document also discusses features like valleys and spurs, encouraging users to engage with a test at the end.

1. Contours
These slides will slowly tell you about contours wait until
you see the NEXT  button to move on.
NEXT 
Click the NEXT only when you are ready to move onto the next slide

2. Relief or shape of the land is shown
by Contours XXXX
xxxxxx
• Contours are those light
brown or orange lines you XXXXX
can see on OS maps.
• A contour line is an
imaginary line that joins
points of equal height
above sea level.
• The lines are numbered
giving the height above sea
level in metres.
• On an OS 1:50000 map the
contours will be drawn for
every 10 metre rise.
Although on this map they
are every 3m so always NEXT 
remember to check.

3. What use are contours?
• They can be used to learn about the
shape of the land (the relief).
• A map with only a few contour lines will be
flat (and often low lying)
• If a map has lots of contours it is a
mountainous or hilly area.
• The actual pattern of the lines will tell you
more detail about the area too.
XXX NEXT 
XXX
XXX

4. • It is important to remember that the closer
together the contour lines the steeper the
slope.
XXXX
Steep slopes
XXXX
Area that is
flatter with
only a gentle
slope
XXXX
•Let’s have a look at why that is. NEXT 

5. • This is the side view of a hill.
Let’s see where this hill reaches these heights
Now let’s plot those points XXXX
Now if we plotted those points on paper.
300m
250m
200m
150m
100m
Sea level
See how these lines are closer together on the steeper slope NEXT 

6. Let’s look at some other examples
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7. Think where is the steepest slope on this island?
Click here to see if you’re right
xxx
200
150
100
50
XXXX
XXXX

8. Steepest slope –
contour lines are closest
together
xxx Sparrow point
227
200
. 76
150
100
50
Sometimes spot heights can be shown as a dot with a note of
XXXX
the height of that particular place. XXXX
A trigonometrical point (or trig point) shows the highest point in an
area (in meters) and is shown as a blue triangle NEXT 

9. You can spot other features by the
shape and pattern of the contours
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10. A valley may look like this…
150
120
90
Often with a river running down through the valley
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11. However a spur can look very similar !
90
120
150
But here the heights are increasing in the opposite
direction – always double check which way the
NEXT 
contours are increasing or decreasing.

12. Valley Spur
150
90
120
120
90 15
0
NEXT 

13. Now Try your hand at a short test or
click on the return button to re-run this
presentation.
For test
click here RETURN