A cross section shows contours joining areas of equal height above sea level, with steep slope lines drawn close together and gentle slopes more spread out. To draw a cross section, dots are placed at the correct heights and smooth lines join the dots. Gradient is calculated by taking the difference in vertical height between two points and dividing it by the actual distance between them on the map scale. Intervisibility refers to whether two points can see each other based on the landscape features between them.

1. CROSS SECTION
David Mzura-Chima

2. Contours join
areas of
equal height
above sea
level
 Steep slopes
lines close
 Gentle
slopes very
spread out

3. Cross-sections

4. Drawing the cross-section
- draw lines up from the base to make a dot at the
correct height then a smooth line joining the
dots…

5. Gradient
 Difference in the
Vertical Height
between two points
DIVIDED by the
actual distance
along the ground
as measured on the
scale of the map
Gradient = 373 - 315m
700m
= 58/700
= 1: 12

6. Intervisibility