バイロイト祝祭劇場
De Waart has also been a frequent conductor of opera, making his first appearance at the Santa Fe Opera (SFO) in 1971, in a production of "The Flying Dutchman". He debuted at the Houston Grand Opera in 1975, the Royal Opera House, Covent Garden in 1976, and the Bayreuth Festspielhaus in 1979. From 1970, he conducted Netherlands Opera (DNO) frequently. In 1980, he directed a "Ring" cycle at the San Francisco Opera.