The most performed ballet is Nutcracker.
Of course, Swan Lake is more famous. But Swan Lake requires excessive technique and giant production of a medium-large ballet company, whereas for Nutcracker, almost any area of US or Europe will have one, two, or four different productions of The Nutcracker at Christmastime—and Shanghai as well.
Here are some pictures I took. It’s beautiful and definitely worth a visit into the Opera House during Christmas—every year.