The Holy Monastery of Koutloumousiou is near the capital Karyes, and is dedicated to the Transfiguration of the Saviour. The founder of the Monastery is thought to be a certain Koutloumous, a member of a dynasty of the Seljuks converted to Christianity.

In the 14th century Koutloumousiou was raided by Catalans. In 1393 it was awarded the status of stavropegic foundation. In 1767 it was burnt down by a fire, but was again restored thanks to the assistance of the Patriarch of Alexandria Matthaios II.

The katholikon dates from the 16th century and the bell-towers are works of the 19th century. Koutloumousiou has seven chapels, relics of saints, vestments and many icons. The library contains 662 manuscripts and 3500 printed books.