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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, ... A large concert hall or odeion was given to the Athenians by Marcus Vipsanius Agrippa, the son-in-law and general of Augustus, in the years around 15 B.C. ... The exterior of the building was elaborated with Corinthian pilasters. 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). ... The structure was rebuilt as a lecture hall, with the seating capacity reduced to about 500, and a far more elaborate facade was built at the north, using massive pillars carved in the form of giants (snaky tales) and tritons (fishy tails) (Fig. 54).