The Holy Monastery of Iviron was founded by monks from Iberia (present day Georgia), disciples of Saint Athanasios; namely, John, his son Euthymios, and his nephew George.
The Monastery was built on the ruins of the Holy Monastery of Saint Clement, where in ancient times there existed a temple dedicated to Poseidon.
The Holy Monastery celebrates its feast on the 15th of August, the Dormition of the Most Holy Mother of God.
In a chapel within the Monastery courtyard there is treasured the wonder-working icon of the Most Holy Mother of God «Portaïtissa». This icon appeared miraculously on the waves of the sea, having traveled on its own from Nicea of Bithynia in 1004.
A gold-plated silver candelabrum, in the shape of a lemon tree, burns in front of the icon of the Portaïtissa. A silver oil lamp hangs in front of the Altar Gate of the Katholicon, which moves on its own miraculously at different times, calling the world to repentance.
The library of the monastery is rich with manuscripts, numbering more than two thousand.
In the sacristy the sakkos of the emperor John Tsimiski is preserved.
The Skete of the Honorable Forerunner, which is located close by, belongs to the Holy Monastery.