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Monument of the Eponymous Heroes Across the street from the Metroon lie the remains of the Monument of the Eponymous Heroes (Fig. 21). When Kleisthenes created the democracy in 508/7 B.C., he assigned ... Literary references indicate that the Eponymoi were erected as early as 425 B.C., though the remains here go back no earlier than ca. 330 B.C. ... Amongst the Eponymoi -- for that is what they call them -- are Hippothoon, son of Poseidon and. . . ."