W. Tyson Joye/National Park Service (Grand Canyon); Jim McMahon/Mapman ® (Map)
1. A canyon is a deep valley with steep sides and the Grand Canyon is one of the biggest canyons in the world. It’s so big that it could hold water from 1.7 billion Olympic-sized swimming pools!
2. How did the Grand Canyon form? Over millions of years rivers carved this deep valley into the rock. Even today flowing water deepens the canyon by the thickness of a sheet of paper every year.