Where can the American flag be flown...

There are ten places where flying the flag around the clock is permissible. They are the Betsy Ross House in Philadelphia; the White House; the U.S. Capitol; the Iwo Jima Memorial to U.S. Marines in Arlington, Virginia; the Revolutionary War battleground in Lexington, Massachusetts; the site of George Washington’s winter encampment at Valley Forge, Pennsylvania; Fort McHenry in Baltimore; the Jenny Wade House in Gettysburg, Pennsylvania (Jenny Wade was the only civilian killed in the Battle of Gettysburg, during the Civil War); the USS Arizona Memorial at Pearl Harbor; all customs points of entry into the United States: and any U.S. Navy ship that is underway.

The flag may also be flown 24 hours a day anywhere it may be flown in the day, provided it is properly illuminated during the hours of darkness.