Eleusis or Eleusina is a town and municipality in West Attica, Greece. It was here that the ancient Greek Eleusinian Mysteries took place, which were initiations held every year for the cult of Demeter and Persephone. Located near the archaeological sites of the city, in Iroon Square, is a post-Byzantine church dedicated to the Prophet Zechariah (not the Old Testament Prophet, but the father of John the Baptist who is also called a Prophet in the Orthodox Church). This church was built over a fifth century church that had fallen into ruin, where it appears instead of initiations into the Eleusinian Mysteries, the Mystery of Holy Baptism took place initiating new Christians.
The original fifth century church was discovered in 1928 by Konstantinos Kourouniotis. It was a three-aisled basilica with a semicircular arch, 15.70m. x 15.40m long in width, with two colonnades consisting of five columns. In addition to the main temple, which had two consecutive splints, the archeological excavation also revealed a square baptistery adjoining the northwest and in its center there is a cruciform fountain built of brick and lined brickwork which mentions "Artemisio" as the baptistery's builder. This type of baptistery resembles similar buildings in Asia Minor and is thought to indicate the existence of relations between the Christian community of Eleusis and other Christian centers. On the north side of the original temple and east of the baptistery, two consecutive sites were identified as changing rooms and the illumination room (photistirion) where the catechumen was anointed with oil and recited the creed prior to baptism.
On the east side of the middle aisle of the fifth century church, the post-Byzantine chapel was erected, which in its present form is a one-room arched basilica. On its west side, above the entrance, there is a bell tower which is a later addition. Its masonry incorporates architectural members and inscriptions from the adjacent archaeological site of the sanctuary of the ancient Eleusinian Mysteries. Also of the same origin are the scattered members found in the surrounding area. The sanctuary of the present church is in the same position as that of the first church and is separated from the main church by a wood-carved iconostasis. The interior of today is adorned with frescoes of the modern era, while the portable icon of Saint Zechariah is dated to 1912. The church celebrates its feast day every year on September 5th.
