Remember to fly your flag at half staff on Wednesday.

Wednesday marks the 18-year anniversary of the 9/11 terrorist attacks on the World Trade Center in New York City, the Pentagon, and United Airlines Flight 93, which crashed in Pennsylvania.

A joint congressional resolution approved on Dec. 18, 2001, designated Sept. 11 as Patriot Day and directed that flags should be lowered to half-staff for the entire day on Sept. 11.