Amounting to 22 most of them follow the style of a domed basilica. They are mainly family churches and are adorned with works by Michael Damascene and Ioannis Skordilis of the 17th century. Many of them have been classified as Preserved as Historical Monuments mainly of the Byzantine period. Except for Panagia Gremiotissa, there is Agios Ioannis Prodromos, Agia Aikaterini, Agios Nikolaos tou Lazarou, Panagia Hrisopigi, Evangelismos, Agios Nikolaos-Agia Varvara, Agios Georgios, Timios Stavros, Panagia Faneromeni etc. FRAGOKLISIA Close to the Elementary school of Chora, there is the only Catholic church on the island which is deserted nowadays. It was built in the late 14th century and belonged to the Diocese of Thera until 1887. Info Agios Georgios and Agia Irnini at the port of Ios have also been classified as Preserved as Historical Monuments Agia Theodoti As in other Cycladic islands, it is said that Ios has 365 churches, like the days of the year. The oldest one is that of Agia Theodoti, in the northeastern part of the island near the bay which has its name. It was founded in the 16th century and is built on the ruins of the ancient temple of Apollo. Just opposite the church there are traces of a Hellenistic tower and an ancient aqueduct.