The Bayreuth Festspielhaus.

Richard Wagner’s Bayreuth Festspielhaus was completed in 1876 according to Wagner’s careful specifications. The 1,925 seat theatre was, at the time, as revolutionary in its design as was the Ring cycle it was meant to house. In the below video from YouTube, the composer’s grandson Wolfgang Wagner takes viewers on a short tour of the interior of the theatre, from auditorium, stage and orchestra pit, describing the innovations of Wagner’s design (there are subtitles).