11 images that bring back the horror of 9/11 attacks

These 11 photos document the enormity, chaos and emotion of 9/11 on every scale, from panoramic views of smoke rising over New York’s skyline to a close-up of the anxious, smudged face of a woman hastening down a street blanketed with ashen dust.

On the morning of September 11, 2001, exactly two decades ago, al-Qaeda terrorists used commercial planes as missiles and crashed into New York’s World Trade Center, the Pentagon and a Pennsylvania field. It was a day which is impossible to forget. Nearly 3,000 people were killed and countless more injured in the terror attack that forever transformed the United States. An estimated 33,000 or more people successfully evacuated the stricken buildings.