The theatre of the Greeks was built on the slope of a hill, thus securing sufficient elevation for the back row of seats without the enormous substructures which the Romans used. If the surface was rocky, semicircles were hewn out, tier above tier, and if it was soft an excavation was made in the hillside and lined with rows of stone benches, the steps being often faced with marble, as in the theatre of Dionysus at Athens. The circular pit thus formed was enclosed by a lofty portico and balustraded terrace, and was assigned to the spectators. The auditorium was divided by broad concentric belts, named diazomata, which served as lobbies, with eleven rows of seats between each, and these were further divided into wedges by transverse flights of stairs between the lobbies, converging on the centre of the orchestra. The latter resembled the passages in a trireme with its banks of oars, and hence were called selides or gangways, the subdivisions, eleven to each section, suggesting as many benches of rowers. Thus Aristophanes bids the audience raise for a certain actor "a splash of applause in good measure, and waft him a nobel Lenæan cheer with eleven oars."
The auditorium was divided, as with us, into several parts, but the assignment of seats was determined not by a money payment, but by rank and other considerations. Thus the rows nearest the orchestra were set apart for the members of the council, while others were reserved for young men, who sat together, or for those who, for whatever reason, were entitled to them. Most of the space was given to the general public, who with these exceptions could make their own choice of seats.
The orchestra was ten or twelve feet below the front row of seats which formed its boundary, a portion of its space being occupied by a raised platform, which presently superseded the altar of Dionysus in the centre, though still known as the thymele. In front of it, and on a level with the lowest tier of seats, was the stage, to which flights of steps led from the orchestra, with others leading to chambers below, and known as Charon's stairways; for they were used for the entrance of spectres from the nether world and for the ghostly apparitions of the dead.
The skené, or house, consisted usually of two stories, to which a third was sometimes added. They were divided by a continuous balcony, adorned with columns corresponding to the dimensions of the orchestra and stage, and contained five doors, through which the actors made their entrances.
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