A view down into the altar (the sanctuary, in English terms) of the Church of the Hundred Doors, or Ekatontapyliani, in Parikia, the chief town of the Greek island of Paros. Beneath the east window is an icon of Christ, marking the throne of the Bishop of Paros-Naxos in the centre of the synthronon, a kind of amphitheatre where the clergy sit during divine service. The tall and pillared canopy, or ciborium, covers the Holy Table. Both of these are rare survivals. The existence of a church here goes back to the fourth century and Helen, mother of Emperor Constantine the Great, but much of the building dates from the sixth and the Emperor Justinian: indeed, the architecture savours of Agia Sophia in Constantinople, which was built around the same time.