ST. JOHN PRODROMOS MONASTERY (Kazimir Popkonstantinov, Rossina Kostova – korina68bg@yahoo.com, Dimitar Nedev) The explorations of the katholikon of the 13th century and the holy spring (cistern) of the monastery continued. The eastern and the western facades of the holy spring were discovered, built of bricks bonded with mortar. It was constructed together with the basilica in the 5th century AD and was situated at 9.50 m to the west of it. The holy spring functioned until 1629 when the monastery was destroyed. Since the end of the 5th century BC a sanctuary of Apollo probably existed on St. John Island.