As Bobbi reminds me, today is the actual date of the adoption of the Declaration.
As John Adams put it:
The Second Day of July 1776, will be the most memorable Epocha, in the History of America. I am apt to believe that it will be celebrated, by succeeding Generations, as the great anniversary Festival. It ought to be commemorated, as the Day of Deliverance by solemn Acts of Devotion to God Almighty. It ought to be solemnized with Pomp and Parade, with Shews, Games, Sports, Guns, Bells, Bonfires and Illuminations from one End of this Continent to the other from this Time forward forever more.*
Sadly, John, everybody remembered the day you signed it, not the day you adopted it.