The Grand Canyon Is Missing a Billion Years — Where Did They Go?

The Grand Canyon is one of the most visited places in America, but hidden inside its walls is a gap in time so large it swallows more than a billion years of Earth's history. In this video, Professor Warren Wilder, a retired geology teacher, walks you through 20 remarkable facts about the Great Unconformity: what it is, how it was discovered, and the theories scientists are still debating, from Snowball Earth to the origin of animal life. Where did a billion years of rock go? Watch to find out. Tell me in the comments which fact surprised you the most, and subscribe for more strange and fascinating facts about the landscapes of America. #GrandCanyon #Geology #GreatUnconformity #SnowballEarth #EarthScience #DeepTime #AmericanGeography #NationalParks #Documentary #Science