Symphony No. 12 in G major, K. 110/75b, by Wolfgang Amadeus Mozart, was composed in Salzburg in the summer of 1771. The symphony was apparently prepared in anticipation of Mozart's second Italian journey, which was to take place between August and December 1771. The symphony is in four movements, the opening allegro being the longest movement that Mozart had written to that date. It is the first of a group of works "painted on a larger canvas and achieving a greater individuality than his earlier exuberant pieces".