June 14 marks the celebration of Flag Day in the United States.

The annual holiday commemorates the adoption of the flag of the Unites States in 1777. The Second Continental Congress adoped the American continental army after reaching a consensus position in the Committee of the Whole on June 14, 1775.

As the week of June 14 is designated as National Flag Week, observance of the holiday involves the president issuing a proclamation urging U.S. citizens to fly the American flag for the duration of that week.

It wasn't until 1916 that President Woodrow Wilson issued a proclamation that officially established June 14 as Flag Day. The day was made a national event by Congress in 1949.

While it is not an official holiday, in 1937 Pennsylvania became the first U.S. state to celebrate Flag Day as a state holiday.

In an effort to celebrate Flag Day, The state of Massachusetts holds one of the longest-running annual parades. Having been started in 1953, the parade celebrated its 59th year in 2010.

In 2009, the 59th Annual Appleton Wisconsin Flag Day Parade featured the U.S. Navy. The largest Flag Day parade is held annually in Troy, New York, which bases its parade on the Quincy, Massachusetts parade and typically draws 50,000 spectators.

Perhaps the oldest continuing Flag Day parade is at Fairfield, Wash. Fairfield has held a parade every year since 1909, and celebrated the Centennial parade in 2010, along with some other commemorative events.