There are plenty of Christian Basilicas on the island of Kos mainly because of its location inside the triangle Palestine, Rome, Kostantinople. Of all the basilicas that were discovered during various excavations on the island, the Aghios Stefanos Basilica stands out as the grandest and best preserved of all. In actual fact this is a complex of two basilicas built on a rock and kept in excellent condition, situated opposite the island of Kastri right on what we could characterize as the isthmus of Kefalos.
According to the Italian professor Laurenzi the basilicas are estimated to have been built between 469 and 554 AD, between the two major destructive earthquakes that hit the island, the second being the cause of the destruction of the monument. The basilica used to be accessed by sea or from the beach. The southern Basilica 22,85 x 15,50 m is larger and earlier than the other. The walls of the entire complex are built of local reddish limestone.