I'll base this on what I'm seeing on Memory Alpha, as I'm in the middle of watching something else at the moment. In "Home", there's a San Francisco Bay Stadium seen where the welcome home ceremony takes place, but no mention of anything related to Candlestick. Perhaps the Auditorium was a novelist's invention. Memory Beta tends to concentrate on written works, not the episodes or films.
WAIT I stand corrected sort of, after finding a single mention in a different article:
In the Star Trek: Enterprise novel Last Full Measure by Michael A. Martin and Andy Mangels, it is established that the first ceremony is, indeed, the founding of the Federation, and that it took place in San Francisco's Candlestick Auditorium on 12 August 2161. Nathan Samuels, Soval, T'Pau, Gral, and others are depicted as signing the Federation Charter. This information, however, is non-canon.