Individual works of the sequence are often performed separately, and indeed the operas contain dialogues that mention events in the previous operas, so that a viewer could watch any of them without having watched the previous parts and still understand the plot. However, Wagner intended them to be performed in series. The first performance as a cycle opened the first Bayreuth Festival in 1876, beginning with "Das Rheingold" on 13 August and ending with "Götterdämmerung" on 17 August. Opera stage director Anthony Freud stated that "Der Ring des Nibelungen" "marks the high-water mark of our art form, the most massive challenge any opera company can undertake."