An ancient Greek open-air auditorium for public (popular) assemblies; the site in Athens (a hill to the west of the Acropolis) where the Ecclesiae were held. It was a semicircular rising ground, with an area of 12,000 square yards, leveled with a pavement of large stones, and surrounded by a wall, behind which was the bema or platform from which speakers addressed the people. It was used from the 6th century BC and remodeled in the 4th century BC.