Pavarotti made his opera début in the role of Rodolfo in "La bohème" by Puccini on April 29, 1961 in the town of Reggio Emilia. Soon he was singing in: the Vienna State Opera. He sang in the United States with Joan Sutherland. In 1965 he sang at La Scala, probably the most famous of all opera houses. He was singing in the famous Franco Zeffirelli production of "La Bohème", with Mirella Freni singing Mimi and Herbert von Karajan conducting. . His first appearance as Tonio in Donizetti's "La fille du régiment" took place at Covent Garden on June 2 of that year. It was his performances of this role that made people call him the "King of the High Cs" (The note C above Middle C is a very high note for a tenor to sing). 