Biomes of the World

Wetlands cover an area of more than 4.7 million square miles (12 million square kilometers) around the world. Every continent except Antarctica has wetlands. Find out more in Wetlands, one of the titles in the Biomes of the World series.

Caves lie beneath the ground of every continent in the world. Cave systems extend for great distances and to extreme depths. Some caves can even be found beneath towns and cities. Find out more in Caves, one of the titles in the Biomes of the World series.