11 Things You Might Not Know About the Grand Canyon on Its 100th Birthday

(via Mental Floss)  Whether you’ve made the trek yourself or seen it on a postcard, the Grand Canyon is one of the most instantly recognizable sights in the United States. But how well do you really know the Colorado River’s most famous handiwork? Here are 11 facts about the Grand Canyon, which Congress declared a U.S. National Park on February 26, 1919.