How big is the Grand Canyon?

Exposing an estimated nearly two billion years of geologic stratigraphy, the Grand Canyon measures 277 miles long, 18 miles at its widest point, and reaches a depth of 1 mile in places as the Colorado River winds through the floor of the canyon that the river carved out. Recent studies indicate formation of the canyon began 17 million years ago. Historical evidence shows the first humans arrived in the area over 10,000 years ago, and Native Americans have lived in the area for 4,000 years and made settlements within the canyon and its caves, The Pueblo people made pilgrimages to the area and considered it a holy site.

The first Europeans to see the Grand Canyon were the dispatched band of conquistadors looking for a river in 1540, led by García López de Cárdenas, a member of the Coronado expedition. In the last 30 years, over 4 million people each year have visited what USA Today lists as one of the seven wonders of the world.