Around 20 million years ago the Colorado River begins to carve into the Grand Canyon at its eastern end, Marble Canyon, and probably exiting via Kanab Canyon. At 17 million years ago the Colorado Plateau begins to uplift and causes the river to cut deeper.
What is the Grand Canyon made out of?
The Canyon itself was carved by the Colorado River and the wind that caused the surface of the sedimentary rocks to become exposed and erode over time. The erosion of the Grand Canyon by winds, rains and the amazing strength of the Colorado River created the marvelous views and exposed magnificent caves.
How many people have fallen into the Grand Canyon?
About 4.5 million people visit the Grand Canyon each year, and an average of 12 people die there annually, according to park statistics. The deaths can be attributed to anything from natural causes, medical issues and suicide to heat, drowning and traffic crashes.