The most important building of the Protaton in the village of Karyes is the church dedicated to the Dormition of the Mother of God. It is the oldest surviving katholikon in Mount Athos and is designed as a three-aisled basilica with two narthexes. The church interior is decorated with frescoes by Manuel Panselinos, which are considered masterpieces of Byzantine art and among the most significant works of the Macedonian School of painting.

During the restoration of the church, the reinforced-concrete roof and the northern covered walkway with its flying buttresses were removed and a wooden saddleback roof with lead coating was erected. Moreover, all exterior surfaces were cleaned and regrouted, and the masonry was reinforced using metal rods.