The region where the Grand Canyon now lies begins to shift ... At the very bottom of the canyon lies the Vishnu Schist, a hard rock originally deposited mainly as sediments some 2 billion years ...

The Grand Canyon is the biggest canyon on earth: 277 miles long, 10 miles wide, and a mile deep. It contains some of the oldest exposed rock on earth, Precambrian Vishnu schist, formed 1.7 billion ...

Explore incredible discoveries in Grand Canyon National Park, from fossils to burial sites, and discover what hides beneath ...