Across
1
Large area covered with trees
3
Half of the Earth
4
Largest river in South America
6
Chain or group of islands
7
Largest hot desert in the world
8
Deep narrow valley with steep sides
9
Where river meets the sea
13
Line dividing two countries
Down
2
Flat elevated area of land
5
Low area between mountains
6
Region surrounding the North Pole
10
Ridge of rock or coral near the surface
11
Region between the two tropic lines
12
Large body of water partly enclosed by land