Teatro alla Scala, or La Scala, in Milan is arguably the most famous opera house in the world. Opened in 1778, it was built on the site of the church of Santa Maria alla Scala. The theater is renowned for its incredible acoustics, achieved through its classic 'horseshoe' shape and the use of wood in the ceiling and galleries. Historically, the floor of the theater was not filled with seats; instead, it was an open space where the audience stood, talked, and even ate during performances. A unique tradition at La Scala is the 'Loggionisti'—the passionate and notoriously critical fans who sit in the highest gallery (the loggione). They are known to boo even the most famous performers if they feel a note is missed. Most of Italy's greatest operatic works, including many by Verdi and Puccini, received their premieres here.