Patriot Day, holiday observed in the United States on September 11 to commemorate the lives of those who died in the 2001 terrorist attacks on the World Trade Center in New York City and the Pentagon in Virginia and those who perished when the hijacked United Airlines Flight 93 crashed in Pennsylvania.

Resource links:

• https://www.timeanddate.com/holidays/us/patriot-day
• https://www.congress.gov/107/plaws/publ89/PLAW-107publ89.htm