The Fortezza of Rethymno occupies a hill that has never quite stopped being fortified. The ancient Greeks built an acropolis here, with a sanctuary to Artemis. The Byzantines added walls. Then came the Venetians, who, rattled by the Ottoman seizure of Cyprus in 1571, decided something more formidable was required.

The result, completed in 1580, was a star-shaped fortress with a perimeter of 1,300 metres, three gates and six ramparts. Its construction drew on 107,142 Cretan labourers and over 40,000 animals. When the Ottomans took Rethymno in 1646, they wasted little time building a mosque inside, right on the site of a demolished Catholic church.

VoiceMap's self-guided audio tours lead you through the Fortezza's gates, tracing its layered occupations from Venetian arsenals and a governor's house to Ottoman hammams and a domed mosque still standing at the fortress's heart.