Patriots’ Day

Patriots’ Day (also spelled Patriot’s Day in Maine) officially recognizes the start of the American Revolutionary War, specifically the Battles of Lexington and Concord (and Menotomy) on April 19, 1775.
It is observed annually on the third Monday in April in most recognizing states. However, some states adhere to the exact date of April 19 (if it falls on a weekday, or otherwise observed then).