The monastery of Agios Ioannis Siderianos is located on the southwest side of the island, in Halakas. The date of its foundation and operation remains unknown, although in documents you mention from 1582. Its architecture is royal after the dome and this church is spacious enough, very well preserved and surrounded by many cells of different dimensions, to accommodate its faithful. . The icon of St. John, located inside the church, is a very old work and is probably the work of the Evangelist Luke.
This monastery owes its name to a miracle of Agios Ioannis. According to popular tradition on the day of the feast of the Saint pirates appeared and the people to save themselves from their raid, was locked inside the church and with prayers and cries begged the Saint to iron the door so that the pirates could not enter. Their prayers were answered and finally the pirates could not open the door. An enraged pirate then climbed into the dome of the church, marked the faithful and attempted to shoot them.Then, the Saint paralyzed his hand and the weapon fell inside the church, where it is kept to this day, along with other religious objects.
The miracles of the Saint did not stop there. During World War II, a British warship fired a shell at a German fort in the area, which was stuck in the church wall. The shell did not explode and you can still see it inside the church today.