AT A GLANCE
Why go?
Guarding the mouth of Heraklion's old Venetian harbour since 1540, the Koules Fortress is the unmistakable sentinel of Crete's capital. Its massive limestone walls—up to 8.7 metres thick at some points—have weathered centuries of relentless seasiege, and today house a multimedia exhibition tracing the history of Candia's fortifications, the legendary Siege of Candia, and underwater discoveries from Cretan waters.↗↗
Built by the Republic of Venice between 1523 and 1540 to protect a port of immense strategic and commercial importance, the fortress contains 26 vaulted chambers that once served as barracks, prisons, granaries, and a bakery. Marble reliefs of the winged Lion of Venice still adorn its gates, and the upper ramparts offer sweeping views across the harbour to the city skyline.↗↗
A Fortress Built Against the Sea
The site had been fortified since at least the Arab occupation in the 9th or 10th centuries, and by the Byzantine period a tower known as Castellum Comunis stood on the mole. An earthquake in 1303 destroyed it, and although repairs followed, Venetian engineers eventually decided the old structure was beyond saving. In 1462 the Senate in Venice approved a programme to modernise Candia's defences, and construction of the Castello a Mare began in earnest in 1523. Old ships were deliberately filled with stone and sunk to create a wider breakwater platform; massive blocks were hauled from quarries on the nearby islands of Fraskia and Dia. Fourteen years later, the fortress that stands today was finished.