La Scala, abbreviation in Italian of the official name Teatro alla Scala, is a famous opera house in Milan, Italy. The theatre was inaugurated on 3 August 1778 and was originally known as the Nuovo Regio Ducale Teatro alla Scala (New Royal-Ducal Theatre alla Scala). The premiere performance was Antonio Salieri's Europa riconosciuta.
Most of Italy's greatest operatic artists, and many of the finest singers from around the world, have appeared at La Scala. The theatre is regarded as one of the leading opera and ballet theatres globally. It is home to the La Scala Theatre Chorus, La Scala Theatre Ballet, La Scala Theatre Orchestra, and the Filarmonica della Scala orchestra. The theatre also has an associate school, known as the La Scala Theatre Academy (Italian: Accademia Teatro alla Scala), which offers professional training in music, dance, stagecraft, and stage management.
Teatro della Scala, shares with the Bolshoi Theatre in Moscow, Russia, the distinction of having the greatest number of tiers. Each has six, with the topmost being nicknamed the Galoirka by Russians.
The Bolshoi Theatre is a historic theatre in Moscow, Russia, originally designed by architect Joseph Bové, which holds ballet and opera performances. The Bolshoi Ballet and Bolshoi Opera are among the oldest and best-known ballet and opera companies in the world. It is by far the world's biggest ballet company, with more than 200 dancers.
According to wikipedia