Across
1
Low-lying land surrounded by higher ground
3
Region between the two tropic lines
4
Body of water surrounded by land
6
Ridge of rock or coral near the surface
7
Wearing away of land by water or wind
Down
2
Landform where river meets the sea
3
Cold treeless Arctic plain
5
Flat grassland in tropical regions
8
Total number of people in an area
9
Large area covered with trees
10
Deep narrow valley with steep sides
11
Large slow-moving mass of ice