September 11, 2001 is one of the most recognizable dates in modern history. Many people in the United States will be able to tell you what happened on that day: two planes flew into the World Trade Center in New York City, one more hit the Pentagon, and a fourth plane was en route to Washington D.C. before crashing into an empty field in Pennsylvania.

The Brightest Spot on the Mountain: Injured Veterans Climb Grand Teton to Honor Those Who Died on 9/11