A spectacular interactive, panoramic view of the Budapest Opera House brought back memories of my first experience of the genre. (Click on any small picture in lower left corner, then use the cursor to rotate it for different views.) Unlike the usual relationship between nostalgia and today's reality, in this case, the renovated neo-Renaissance building now is far superior to the shabby conditions in olden days.
With its appealing architecture by Miklós Ybl, and richly decorated by leading artists of the day, the opera house opened in 1884. Just as in San Francisco and many other cities both in Europe and the U.S., a resident company in a permanent venue came after traveling opera troupes performing in theaters; in case of Budapest, that went back to 1835.
Seating 1,261, the opera house was declared by a group of international engineers to have the third best acoustics in Europe, after La Scala in Milan and the Palais Garnier in Paris. (I don't agree about Palais Garnier, but that's just an unscientific opinion.)
The Operaház is certainly one of the busiest, in the U.S. only the Metropolitan can come close to Budapest's century-plus repertory of 45 to 50 operas and about 130 annual performances.