The existence of a theater in Acharnes was known from two inscriptions that had been found earlier in the area and today are kept in the Epigraphic Museum and the Archaeological Collection of Acharnes. The Ancient Theater of Acharnai was revealed accidentally in 2007 during the excavation for the construction of a building on a private plot at 21 Salaminos Street, in the center of the modern Municipality. The construction of the theater dates to the 4th century BC, while the site was in use until Roman times.