Fortezza Castle
It is possible that the hill on which the Fortezza is built was once an island joined to Crete by a narrow strip of land. Over the centuries the channel silted up and the hill became part of the Cretan mainland. Later, the hill of Paleokastro ("Old Castle") was probably the site of the acropolis of ancient Rithymna with its Temple of Apollo and Sanctuary of Artemis, although this has not been proven to date.
During the Second Byzantine Period (10th-13th c. AD), a small walled settlement was established east of Paleokastro hill, the Castrum Rethemi or Castel Vecchio or Antico Castello ("Old Castle") as the Venetians later called it.