The Munich Festival Theatre was to be a huge monumental building incorporated in the urban structure (by means of alteration of the surrounding area). A new boulevard would lead from the city centre to the new theatre and the theatre’s site was to be connected to the royal gardens by a splendid arched bridge. The opera house itself would rise on a series of levelled platforms on the higher bank of the Isar. The design was never executed but in 1866, Semper made a model (that has been preserved), which gives a lot of information on the building’s features.
The opera house was uncommonly wide. Its two extensive wings made it look very elegant despite the colossal dimensions. Semper expressly wanted his design to clarify the different functions of the various parts of the building, without neglecting the composition of the whole. All parts had to come together in an organic union. The theatre was to be a worthy temple of Wagner's art and at the same time a structure adapted to Ludwig's expensive taste.
Semper's design shows a classical building with overtly Roman influences. It contained a large arched vestibule, a foyer, a monumental staircase, several halls for parties and concerts, and plenty of room for the technical equipment. Above the main entrance, a balcony for the king was incorporated. Surrounding the theatre was a beautiful garden with fountains. The auditorium was semicircular, reminiscent of the ancient cavea. The seats were arranged on two levels. It was an enormous room: 43.8 metres wide and 38 metres deep. The distance to the stage was huge. In the back wall of the auditorium was installed a portico-like colonnade with the royal box in its centre.
Semper conceived a double proscenium arch (a smaller frame set behind the main frame that separates the stage from the auditorium). This feature would be elaborated by Brandt in the Bayreuth Festspielhaus design. Brandt set the smaller frame somewhat to the back. Arranged like that, the double proscenium created, by means of accelerated perspective, an optical distortion of figures on the stage; everything, people and distances, seemed larger than they actually were.
Semper also supplemented the footlights (a row of light placed at the front edge of the stage that illuminated actors and set from the bottom up) with additional lights from above and from the sides to create a more natural effect. At the time, gas was used to light the stage.
One of the main problems of the design was the connection of the very large auditorium with the comparatively small picture-frame (although unusually wide in itself). It would take the theatrical judgement of Brandt to find a satisfactory solution to the problem. However, as Habel and Izenour remark, Sempers attempt to unite an amphitheatrical auditorium with a Romantic picture-frame stage was entirely new and would prove a landmark in theatre history. Semper's second problem had to do with the auditorium itself. The architecture was so dominant, especially since he adopted Roman-like parallel side walls with arched entrances and columns, that it would distract the audience from the performance.
The two designs for the Glass Palace theatre were not so different from the monumental design. Of course the former was to be temporary (and therefore of wood), and a lot smaller. Both the A and B project show a semicircular arrangement of seats, with all seats on the same plane, except for the King's Loge. Plan A provides far better sight lines than plan B and the monumental theatre, due to the diminished proportions of the construction. In plan B, a number of seats on both sides of the gallery provide a rather bad view onto the stage.