Behind I.N. The early Christian basilica of Agios Andreas Eresos is in ruins, behind which he was buried in 740 AD. Saint Andreas, archbishop of Crete, who died at sea in front of Eresos passing through Constantinople. The church was probably dedicated to the holy martyr Anastasia, but it remained known as the basilica of Saint Andrew. It is one of the largest Early Christian basilicas of Lesvos with a rectangular floor plan.
It was discovered after excavations by the monks of I.M. Pithariou in 1884-1885. It has a three-aisled arrangement and consists of a narthex, mainly a temple and a sacred platform. The arch of the sanctuary is inscribed circular on the inside, while on the outside it is multi-sided, a type that came from Syria. An inscription in the passage of the western part of the floor that mentions the bishop John, who represented the Lesbians in the 3rd Ecumenical Synod, as well as the mosaics that decorate the floor of the temple, testify to the dating of the temple at the beginning of the 5th century perhaps and earlier.
At a sufficient height, the walls of a small old chapel dedicated to St. John the Forerunner are also preserved, as well as auxiliary areas of the church. At the back of the church there is still today the mausoleum with the cenotaph sarcophagus of St. Andreas Crete.
