The castle of Chryssi is identified as the Byzantine city of Moglena, seat of the homonymous ?thema? and bishopric, dating from the 11th c. It contains an area of approximately 40 acres. On the southeastern side there is a round, a square and a rectilinear, with a semi-circular front, tower. To the south survive two more analogous towers. The chronology of the castle, dates from the 10th to the 13th century. Inside, a large basilica, believed to be the episcopal church of Moglena, is excavated.