Archaeological excavations carried out between 1984 and 1994 in the Castle of Mytilene by the University of British Columbia and directed by Caroline and Hector Williams revealed a previously unknown sanctuary of Demeter and Kore of late classical/Hellenistic date and the burial chapel of the Gattelusi, the medieval Genoese family that ruled the northern Aegean from the mid-14th to mid-15th centuries of our era. The Demeter sanctuary included five altars for sacrifices to Demeter and Kore and later also to Cybele, the great mother goddess of Anatolia. Among the discoveries were thousands of oil lamps, terracotta figurines, loom weights and other dedications to the goddesses. Numerous animal bones, especially of piglets, also appeared. The Chapel of St. John served as the church of the castle and as a burial place for the Gattelusi family and its dependents. Although conversion to a mosque after the Ottoman capture of the city in 1462 resulted in the destruction of many graves, some remained. The great earthquake of February 1867 damaged the building beyond repair and it was demolished; the Ottomans built a new mosque over the ruins to replace it later in the 19th century.