The design was adapted by Wagner, without the architect's permission, from an unrealised project by Gottfried Semper for an opera house in Munich, and built under Wagner's supervision. Its construction was funded principally by King Ludwig II of Bavaria. The foundation stone was laid on 22 May 1872 (Wagner's birthday). The building was first opened for the premiere of the complete four-opera cycle of Der Ring des Nibelungen (The Ring of the Nibelung), from August 13, 1876 to August 17, 1876.
Only the entry façade exhibits the typical late-19th-century ornamentation, while the remainder of the exterior is modest and shows mostly undecorated brick stone.
The most famous and significant feature of the Festspielhaus is its unusual orchestra pit. It is recessed under the stage and covered by a hood, so that the orchestra is completely invisible to the audience. This feature was a central preoccupation for Wagner, since it made the audience concentrate on the drama onstage, rather than the distracting motion of the conductor and musicians. The design also corrected the balance of volume between singers and orchestra, creating ideal acoustics for Wagner's operas, which are the only operas performed at the Festspielhaus. However, this arrangement has also made it the most challenging to conduct in, even for the world's best conductors. Not only is the crowded pit enveloped in darkness: the acoustic reverberation makes it difficult to synchronise the orchestra with the singers. Conductors must therefore retrain themselves to ignore cues from singers. Most, if not all, of the festival's conductors have found the Festspielhaus venue the most challenging of their careers.
The Festspielhaus also features a double proscenium, which gives the audience the illusion that the stage is further away than it actually is. The double proscenium and the recessed orchestra pit create, in Wagner's term, a "mystic gulf" between the audience and the stage. This gives a dreamlike character to performances, and provides a physical reinforcement of the mythic content of most of Wagner's operas.
The Festspielhaus remains the venue of the annual Bayreuth Festival, during which Wagner's operas, such as the Ring cycle and Parsifal, are given on a repertory basis.