Eighteen years after coordinated attacks, many paid tribute to those who were victims of terrorist attacks on U.S. soil on Sept. 11, 2001.
Approximately 3,000 people were killed when terrorist-piloted planes slammed into the World Trade Center, the Pentagon and the field in Pennsylvania. More than 6,000 others were injured. According to the Associated Press, more than 51,000 people have applied to a compensation fund for those who suffered from illnesses related to the attacks.
First responders, primarily police and firemen, are also remembered, as many of them have died since the attacks.
The gallery below is a reminder of the events from that day, and how it is remembered today.