 It also has a lot of really important announcements that we tend to think are our cornerstone of what the United States is and what it means. The event dates back to 1969 and involves the audience interacting with reenactors. It also has some really important principles that we tend to think of as Americans as our founding principles. After it's over, everyone's invited inside to see the founding document firsthand. Mike Murillo, WTOP News.