On July 14th 1789, a Parisian mob gets a hold of 30 000 guns and storms the Bastille prison, a symbol of despotism, an incident that will symbolically mark the beginning of the French Revolution.
Ironically, the Bastille only held 7 prisoners at the time, including 3 aristocrats treated for madness, all the political prisoners had long been moved to other jails around the country.
The Federation party a year later started the long tradition of the Bastille day, at the time France had become a constitutional monarchy which Louis XVI recognized, he would break his promise a few months later and end as you all know.
A military parade is organized every year on the Champs Elysee as well as celebrations around the country and fireworks.
Famous pensioners of the Bastille included: Voltaire, Beaumarchais and the Marquis de Sade amongst many others.
Vive la Revolution!
(although I am a Bonapartist)