Fall of the Bastille
From Thomas Jefferson Encyclopedia
The fall of Bastille occurred on July 14, 1789, and the event proved to be a potent symbol of the fight against despotism and an opening stage for the French Revolution. On May 5, Louis XVI called the Estate-General, and by July 9th, the group re-formed as the National Assembly and began to act as a parliament and draft a constitution. Also, bread prices were at a twenty year high causing food riots closer to Paris and troops were gathering in the city. By July 12, when news hit Paris that the pro-Assembly finance minister, Jacques Necker, was dismissed, people began to gather and find ammunition to prevent the dissolution of the National Assembly.
The Bastille was not only a prison but it was a storehouse for ammunition. A crowd stormed the prison on July 14 with the garrison striking back. The troops were overwhelmed and terms for surrender were made. On the 15th, Marquis de Lafayette arrived to command the National Guard to help restore order. Bastille's fall helped pave the way for troop withdrawal and further reforms by King Louis XVI.
The fourteen-century prison actually held only seven prisoners and around 80 invalids that night, and it was slated to be demolished and Lafayette got volunteer wreckers to finish the job. Jefferson visited the prison twice, and Dumas Malone states Jefferson did visit the Bastille after the event. Jefferson wrote about that night in a letter to John Jay on July 19, 1789 and in his Autobiography.
Primary Source References
1789 July 19. (Jefferson to John Jay). "The demolition of the Bastille is going on...we cannot find with certainty that any body has been killed but the three beforementioned, and those who fell in the assault or defence of the Bastille. How many of the garrison were killed no body pretends to have everheard. Of the assailants accounts vary from 6. to 600." 
1789 July 21. "Gave for widows of those who were killed in taking the Bastille 60."
1821 January 6. (Autobiography). "They found a great collection of people already before the place [Bastille], and they immediately planted a flag of truce, which was answered by a like flag hoisted on the Parapet. The deputation prevailed on the people to fall back a little, advanced themselves to make their demand of the Governor, and in that instant a discharge from the Bastile killed four persons, of those nearest to the deputies. The deputies retired. I happened to be at the house of M. de Corny when he returned to it, and received from him a narrative of these transactions. On the retirement of the deputies, the people rushed forward & almost in an instant were in possession of a fortification defended by 100. men, of infinite strength, which in other times had stood several regular sieges, and had never been taken. How they forced their entrance has never been explained. They took all the arms, discharged the prisoners, and such of the garrison as were not killed in the first moment of fury; carried the Governor and Lt. Governor to the Place de Greve...cut off their heads, and sent them thro' the city in triumph to the Palais royal."