On September 11, 2001, people on the East Coast of the United States woke up to a brilliant blue sky and bright sunshine. The day was filled with promise that it would be a lovely one. Little did anyone know the day would end as one of the darkest and deadliest in United States history.

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As thousands of people filed into the World Trade Center towers that day, none of them could have imagined the events about to take place. American Airlines Flight 11 slammed into the north tower at 8:46 a.m., tearing a hole into the building which stretched from the 93rd to 99th floors. 17 minutes later, at 9:03 a.m., a second plane flew into the south tower crashing into the 77th through 85th floors.

The United States was under attack and the attack was far from over. About a half-hour, after the second plane hit the south tower of the twin towers, American Airlines Flight 77 slammed into the west side of the Pentagon in Arlington, slicing right into the building before the fuel tanks on the plane exploded, causing two massive fireballs to blast off.

A fourth plane was hijacked, this one was United Airlines Flight 93 and it crashed into a field near Shanksville, Pennsylvania which is only a short flight away from what many believe was the actual target - a building in Washington, D.C.

Nearly 3,000 people lost their lives that fateful day and hundreds more have died in the years since as a result of the attacks. 2021 marks the 20th anniversary of the September 11, 2001 attacks, and is it is so important that none of us forget that day and that we do our part to make sure our children and grandchildren are also aware so that we can fight to make sure nothing like this ever happens again.

On this 20th anniversary of September 11, 2001, let's pause to look back at some of the photos released that day and the days that followed so that we may never forget.

25 Images That Remind Us of the Devastation Caused on September 11, 2001

NEVER FORGET: Images from 9/11 and the days after

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