It is considered the oldest monastery in Crete, as it was founded in the mid-11th century. Its founder was St. John the Stranger or Hermit (Agios Ioannis Xenos or Erimitis), who lived in the cave, where you will see the temple dedicated to him (celebrates on September 20). The surrounding caves housed many hermits, while some monks lived in the cells of the monastery. When the coasts of Crete were targeted by the pirates, the monks were forced to move to a more remote place, so they abandoned Katholiko.
The monastery is now ruined and can be accessed through a trail that that starts from the monastery Gouverneto (20-30′ walking). In the monastery you will see the Cathedral of St. John the Hermit and his Cave, the ruined monks’ cells and the impressive old bridge that crosses the river. Beneath the floor of the bridge there are still several storage rooms.
Moreover, if you keep walking for 10 minutes to the sea, you will find yourself in a wonderful small fjord with turquoise waters, where there are the ruins of the old harbor of the monastery. Moreover, nearby there is a large rock with a ship-like shape. According to the legend, the rock is a pirate ship, which was petrified after the curses of the abbot of Katholiko.