Vienna State Opera
The opera house was the first major building on the Vienna Ringstrasse commissioned by the Viennese "city expansion fund". Work commenced on the house in 1861 and was completed in 1869, following plans drawn up by architects August Sicard von Sicardsburg and Eduard van der Nüll. It was built in the Neo-Renaissance style by the renowned Czech architect and contractor Josef Hlávka.
Yerevan Opera Theatre
Armenian National Academic Theatre of Opera and Ballet named after Alexander Spendiaryan (, "Aleksandr Spendiaryani anvan operayi yev baleti azgayin akademiakan tatron", or simply known by locals as Օպերա, "Opera") in Yerevan was officially opened on 20 January 1933, with Alexander Spendiaryan's Almast opera performance. The opera building was designed by the Armenian architect Alexander Tamanian. It consists of two concert halls: the Aram Khatchaturian concert hall with 1,400 seats and the Alexander Spendiaryan Opera and Ballet National Theatre with 1,200 seats.