The Mithraeum of the Circus Maximus was discovered in 1931 during work carried out to create a storage area for the scenes and costumes of the Opera House within the Museums of Rome building.
I think it would be helpful to include visiting information... I’m under the impression that some of the Roman mithraea require prior registration. Getting such info from people who have been would seriously help.
It will indeed be helpful to have up-to-date information from anyone who has just visited a temple. However, since opening hours can change depending on demand, season, holidays, and other factors, I would also recommend always checking the official website or with operators before visiting.
