Capitol Theater (Düsseldorf) is the largest theatre in Düsseldorf, North Rhine-Westphalia, Germany. Background The building, which is over 100 years old, is a former Straßenbahn depot of the Rheinbahn, which was converted in the early 1990 into the theatre. It was inaugurated in 1996 with a performance of the musical Grease. Theatres in Düsseldorf