The Reneissance Fair is an event metnioned on WCTR in GTA San Andreas.
On WCTR, in the begginging of the game theres a radio announcment about a man that has bought a catapult at the Reneissance Fair, and wanting to kill his boss. He seems to be arguing about the qualaty of it and says that it should "have a clearly visible label on it" abnd says that he'll sue the man who sold him that, and become rich.
It is unknown where it is or was located, but it was probably an event before Carl Johnson came to Los Santos, and it was probably a yearly event. Even if so, its location remains unknown.