This is the most important attraction of the monastery of St. John and it is considered to be the biggest museum in the Aegean. It was inaugurated in 1988, nine hundred years since the founding of the monastery. In the museum's showcases there are valuable treasures such as the parchment of the Crimson Code (late 5th early 6th century) and the edict of Alexios Komninos (1088) with which he gave the whole island of Patmos to Saint Christodoulos.
In the museum you will also see old books, manuscripts, silverware, vestments, the painting of Christ Elkomenos (probably created by of El Greco), a picture of Andreas Ritzos (15th century) and the mosaic icon of St. Nicholas (11th century). Moreover, the collection includes 18th and 19th century manuscripts, a Gospel of the 12th century, a 17th century chandelier with dragons, inscriptions, friezes and fragments from the temple of Artemis which was here before the monastery was built.
