Back in the 1930’s, John Christie—a wealthy English music lover—married a Canadian soprano, built a small theater in the gardens of his 16th-century country house in the Sussex Downs, and founded the Glyndebourne Festival, an annual summer season of opera. Today, Christie’s grandson Gus (himself married to a soprano, the scintillating American diva Danielle de Niese) heads the prestigious festival, which celebrates its 80th anniversary this year. From May through August, Glyndebourne presents six operas, meticulously produced, and staged by a host of directors, from traditionalists (Franco Zeffirelli) to gleeful iconoclasts (Peter Sellars). Above all, the festival is famous for engaging great singers early in their careers, among them Joan Sutherland, Luciano Pavarotti, and Renée Fleming. Yet not all the magic occurs onstage. Performances, which begin in the afternoon, include a leisurely dinner intermission—long enough for a picnic on the lawn. This season’s new productions include Giuseppe Verdi’s La Traviata and Richard Strauss’s Der Rosenkavalier, led by Robin Ticciati, the company’s dashing new music director.