Description: We deal with the ruins of the catholic church of Hagios Markos built during the period of the Frankish rule in the southwest of the Katholikon of Kaisariani Monastery. Its position offers a view till Saronikos, which has also been mentioned in Michael Choniates’ epistles. The first Christian center of the Monastery was founded in this exact position known as the “Cemetery of the Holy Fathers”. The area is called Frangomonastiro after this catholic church. In the 11th century the monastic center was transferred to its present safer position with the foundation of the Katholikon of Kaisariani Monastery.