Propylaea of the Sanctuary. A monumental staircase leads to a Ð-shaped stoa and a wall with five door openings. The lateral wings of the stoa had hexastyle prostyle facades (stoas with six columns) with pedimental roofs. A room opened behind each wing of the stoa; the room in the west wing was followed by three smaller chambers and that in the east wing by one. They were used for depositing the votive offerings to the goddess. These chambers opened onto an interior peristyle courtyard with a portico on three sides in which an altar stood. At a later period, in around 200 AD, the open fourth side of the courtyard was closed by an Ionic portico. The Propylaea were also built of poros stone and bear polychrome traces on the upper part. It dates to the 4th c. BC.