Why do mountains get bigger? Where is the hottest place on Earth? Why are oceans and lakes changing size? How does a river carve out a valley? Why are tropical rain forests vital for the future of the planet? 101 Facts About Our World answers all these questions and more about our amazing world. Best of all, these books are packed with spectacular photos that show the stunning beauty of Earth's natural features. Learn how mountains are formed and what causes an avalanche. In 101 Facts About Mountains, you'll also find fascinating facts about the plants and animals that survive on mountain summits.