In larger theatres the auditorium was almost always divided into several storeys by gangways. These gangways ran round the auditorium concentrically with the seats, and their object was to facilitate the circulation of the public; they were therefore of considerable breadth (compare Fig. 153), and sometimes two such gangways were put close to each other, one higher and one lower, so that the public could circulate easily on them without pushing each other. The separate seats were everywhere connected by steps. Although the arrangement of the whole auditorium with its raised seats was that of a circus, yet the seats were far too high to be used as steps also, and these had to be specially constructed. They were of two kinds; small steps in the direction of the seats, the object of which was to enable people to mount from one seat to the next, and the principal staircases, which intersected the seats through their whole extent from top to bottom, and formed, as it were, radii of the circle represented by the auditorium. The number of these staircases was larger or smaller as occasion required; sometimes the number was doubled at the top, where the distances increased, by introducing a third staircase between each pair; sometimes the staircases which began below did not continue at the top, but there was a change in the radii. It was most common, however, for these staircases to intersect the whole theatre right up to the highest seats, and thus to divide the whole auditorium into a number of wedge-shaped divisions, which, in fact, received the designation of wedges ([Greek: kerkides]). Sometimes these wedges had special names, being called after statues which were placed there, as, for instance, in the theatre at Syracuse, and these designations facilitated the finding of places. As a rule, the steps were so arranged that there were two to every seat, thus each step was half the height of the seat.
In later times the upper seats led to open arcades; when the ground permitted it, the Romans often laid out walks and gardens on the elevation of the theatre, where the spectators might refresh themselves during intervals; below, near the orchestra, the auditorium was cut off by a wall, which must be so low that the spectators on the first seat could conveniently see the stage, which was raised a good bit above the orchestra. Sometimes the first gangway for the circulation of the public was placed behind this wall, which was bounded by a low breastwork; when this was the case, steps of the first-mentioned kind led up sideways to the orchestra (compare Fig. 153).