Across
1
Cold treeless Arctic plain
4
Raised area of land, smaller than a mountain
6
Height above sea level
9
Largest river in South America
10
Deep narrow valley with steep sides
11
Flat grassland in tropical regions
Down
2
Vast body of salt water
3
Large natural elevation of earth
5
Largest hot desert in the world
6
Chain or group of islands
7
Large area covered with trees
8
Distance north or south of equator