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Odeion of Agrippa Late in the 1st century B.C. the Athenians were given money for a new marketplace by Caesar and Augustus, and the northern half of the old Agora square was filled with two new structures, ... It was a huge two-storeyed structure that must have dominated the square (Fig. 52). The auditorium, with its raised stage and marble-paved orchestra, seated about 1,000 spectators. ... Entry to the Odeion was either from the upper level of the Middle Stoa on the south or through a modest porch at ground level on the north (Fig. 53). Figure 52. Cross section of the Odeion, 1st phase (late 1st century B.C.), looking east.
