It is a church in a cave, which nowadays has been incorporated into the more recent, big church in Thisseion. This small church, which operates as a baptistery, lies annexed in the southern side of the church. Fragments of wall paintings are preserved in it. Many of them have been removed and are displayed in a certain area inside the church. These wall paintings are basically post Byzantine ones, although some of them are dated to the 13th century. The altar still exists in the eastern side of the old church, which is separated from the more recent one with a grating.
For further information see ODYSSEAS