Official website: https://www.operadeparis.fr/en
The official name is the Palais Garnier (named after the architect), but is best known as the Paris Opera. The organisation ‘Opéra national de Paris’ performs here and also the Opera Bastille, which opened in 1989. This is the primary site of large-scale opera productions in Paris. The Palais Garnier (or “Opéra Garnier”) is used more frequently for dance and music productions than operas.
Due to a flooding problem during construction, when the foundations broke into a branch of the River Seine, a series of cistern tanks were built to take the water and to equalise the pressure on the foundations, forming a huge underground lake. The ‘catacombs’ described in the Phantom of the Opera are the vaults and walls of the tanks to hold the water.