The sanctuary’s Archaic peribolos was erected in the first half of the 6th cent. BC and takes up an area measuring approx. 40 × 20 m in the southernmost (tallest) terrace of the larger site which the Eleusinion occupies today. The wall of the peribolos, crafted in very well-constructed polygonal masonry, was made up of local poros stone. The entrance to the Archaic peribolos was located on the southern wall, 3 m east of its southwest corner. The length of the peribolos to the east is unknown, because modern buildings now take up this area. Its dimensions are: 22 m W, 26 m N (surviving length), and 28 m S (surviving length).
According to the excavators it was constructed in c.550 BC. During the same period, two wells west of the sanctuary were rendered useless, possibly during works to demarcate the Panathenaic Way during Pisistratus’ rule, when the tyrant of Athens re-established the Panathenaic festival and arranged for the ceremony and the games that accompanied it to be held in the area of the Agora and the Acropolis.
The sacred(?) protrusion on the rock
The upper terrace, where the Archaic peribolos was confined, contains an interesting local physical feature, of apparently devotional importance in the sanctuary: a protrusion of the natural bedrock (height: approx. 80 cm), of an irregular quadrilateral shape (approx. 2 × 3 m) with its upper surface rounded; it protrudes in the western wall of the Archaic peribolos, roughly in its middle. Similar terrain features, rocks, natural protrusions of the ground etc, have known to be objects of worship in the ancient world. These were usually considered as places where mythical events had taken place; quite often such physical features were associated with Demeter and her wanderings. A Roman inscription found inthe site of the Eleusinion refers to a lithos (=stone), possibly the protrusion at this particular spot (Miles 1998, 20-21).
