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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, ... 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, the Odeion of Agrippa and the Temple of Ares. 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.