Advance sales for a production of La traviata at the 2005 festival are greater than any event since the death in 1989 of Herbert von Karajan, the festival's longtime artistic director.
"These seven performances of Traviata are hopelessly overbooked," said box office director Adreas Vrtal.
The production stars Anna Netrebko, Rolando Villaz‹n, and Thomas Hampson.
Sales are also strong for a new production of The Magic Flute, to be conducted by Riccardo Muti; Schreker's Die Gezeichneten; and Pina Bausch's Nelken.
The festival runs from July through August 31, and will include 183 events.