The Greek Orthodox church of Hagios Ioannis Prodromos, St. John the Baptist, is the most prominent monument in the village, its dome, raised on a high drum, dominating the view as seen from the ferry as one approaches the iskele. The church is a short way from the seafront on the first street to the south of the ferry landing.
The present church, built in 1899, is believed to stand on the site of the katholikon of the Byzantine monastery of St. John. The original katholikon was probably built in the eleventh century, and parts of its structure are thought to be incorporated in the present church, which seems to retain the plan of the earlier structure. The evidence for this conclusion is presented by George Mastoropoulos in his Patriarchal Monasteries of the Princes’ Islands.
On the left side of the narthex, or vestibule, a stairway leads down to a small subterranean crypt with a vaulted ceiling. The crypt is dedicated to St. Methodios, for this is believed to be the dungeon in which he was imprisoned by Michael II, and where he remained for seven years before being released by the emperor Theophilos. Grosvenor describes the ordeal that Methodius endured before going to his final rest:
At Antigone, Theodora erected the Church of St. John the Baptist over the cave where the Confessor had been so long confined. In the renovated modern wooden [actually stone and brick] church, still the chief sanctuary of the islanders, little remains of the early edifice. Nevertheless the apse, or eastern portion, is part of the original structure.
