Across
1
Line dividing two countries
4
Cold treeless Arctic plain
5
Raised area of land, smaller than a mountain
6
Largest ocean on Earth
7
Height above sea level
10
Dry land with little rainfall
Down
2
Narrow sea inlet between cliffs
3
One of seven major landmasses
8
Piece of land jutting into the sea
9
Chain or group of islands
11
Ridge of rock or coral near the surface