THE KASTRO OF NAXOS: A VENETIAN CITADEL STILL BEING LIVED IN

Climb from the harbour front of Naxos Town up through the tangle of the Bourgos quarter, and the streets eventually narrow, steepen, and turn to worn marble underfoot. This is the Kastro — the old fortified heart of Chora, built in 1207 by the Venetian nobleman Marco Sanudo, and, remarkably for a medieval citadel, still a genuinely inhabited neighbourhood rather than a museum piece. Behind heavy wooden doors and beneath stone-carved family crests, some of the same Catholic families whose ancestors arrived with Sanudo eight centuries ago still keep houses here today.

A Duchy Built on a Much Older Hill

In 1207, in the chaotic aftermath of the Fourth Crusade's sack of Constantinople, the Venetian nobleman Marco Sanudo led a private expedition into the Aegean and seized control of Naxos and a number of surrounding islands, eventually ruling as many as seventeen of them. He declared himself Duke of the Archipelago, established the Duchy of Naxos, and made the island his capital — a Venetian Catholic lordship that would rule the central Cyclades, in one form or another, for the next three and a half centuries.

Sanudo did not choose his citadel's location arbitrarily. The hill overlooking Naxos's harbour had already functioned as a natural defensive high point for millennia; it is widely believed to have been the site of the Mycenaean-era acropolis connected to the ancient city at nearby Grotta, whose walls still lie partly beneath, and partly submerged beside, the modern seafront just below the Kastro. Sanudo's fortress builders made that older history literally part of the new one: construction reused stone from the pre-existing ancient acropolis on the site, and, in a detail that connects the Kastro directly to one of Naxos's most famous landmarks, some of the marble columns and blocks worked into its walls were taken from the area of the ancient Temple of Apollo, whose surviving doorway, the Portara, still stands on the harbour a short distance away.

A Pentagon of Walls, Towers and Gates

The Kastro's fortification circuit was laid out in a distinctive pentagonal shape, its walls rising directly from the natural bedrock in a near-vertical line with only a slight taper at the base — a deliberate structural choice rather than the more sloped, reinforcing scarp seen in many contemporary fortresses elsewhere. Historical accounts describe an original ring of twelve towers spaced at roughly ten-metre intervals around the perimeter, an unusually dense defensive arrangement reflecting how seriously piracy and the threat of rival powers were taken in the Duchy's early centuries. Three gates originally pierced the walls: Trani Porta, the "Great Gate," on the northern side; Paraporti to the south, which still serves as the main entrance for visitors today; and Piso Paraporti on the south-east, which no longer survives. The complex itself extends across four distinct levels climbing the hillside, and its rounded overall plan makes it, by most local accounts, the only castle on Naxos built to this particular circular form.

At the Kastro's centre, the ruined remains of a tower are traditionally identified as the site of Marco Sanudo's own ducal palace, and, in the same south-eastern quarter, the upper floor of a projecting perimeter tower once held the ducal chapel, known as the Capella Casazza, dedicated to the Immaculate Conception and reserved for Sanudo's personal use — a private place of worship whose foundation is thought to actually predate the Kastro's later, more public Catholic cathedral.

From Duchy to Ottoman Rule, Without Losing Its Character

Sanudo's Duchy of the Archipelago endured, through several changes of ruling family, until the mid-16th century, when Ottoman naval power under Hayreddin Barbarossa brought Venetian rule in the wider Aegean to an end and the Duchy passed under Ottoman suzerainty. What makes the Kastro's story unusual is what happened next: rather than being displaced, the island's Catholic Venetian nobility largely remained in place, continuing to occupy their Kastro mansions, worship in their own cathedral, and educate their children in Catholic schools for generations under Ottoman administration — a genuinely rare instance of a conquered elite's built environment, and much of its social structure, surviving essentially intact across a change of imperial rule that ended Latin Christian political power almost everywhere else in the region.

Inside the Walls: A Small City of Its Own

Within the Kastro's compact footprint, the Venetian Duchy built essentially an entire self-contained administrative, religious and educational quarter, much of which still stands and remains open to visitors. At the centre of the old town, the Catholic Cathedral — formally the Church of the Presentation of the Lord, and often referred to locally simply as the Catholic Metropolis — occupies the Kastro's main square in a Romanesque-influenced medieval form, its marble floor set with memorial stones bearing the carved coats of arms of the island's most prominent Catholic families across five centuries, and housing a notable Byzantine-style double-sided icon depicting the Virgin Mary on one face and Saint John the Baptist on the other.

Immediately next to the cathedral stands the only one of the Kastro's original twelve towers to survive intact: the Tower of Crispi, more commonly known today as the Glezos Tower, named for the Crispi dynasty, the last ruling family of the Duchy before Ottoman rule, whose coat of arms is still carved above its entrance. Local tradition holds that the tower once served as a ducal residence in its own right; more recently, ownership of the tower was transferred to Greece's Archaeological Service for conservation and restoration. A short walk away, the Della Rocca-Barozzi Venetian Museum occupies an eight-hundred-year-old tower-house belonging to one of the Kastro's other prominent noble families, its rooms furnished with period furniture, clothing and everyday objects that give a genuinely intimate sense of how the island's Venetian elite actually lived, generation after generation, inside these same walls.

Education and religion filled out the rest of the Kastro's self-contained world. The Ursuline School, a 17th-century convent institution, educated young women of the Venetian Catholic aristocracy for centuries, while a Jesuit school founded in 1627 taught Catholic boys on the island for roughly three hundred years; that building today houses the main Archaeological Museum of Naxos, home to a genuinely world-class collection of Early Cycladic marble figurines and other finds spanning the island's full archaeological history, from prehistoric to Byzantine. Close to the Kastro's restored 13th-century Orthodox cathedral, meanwhile, the Mitropoleos Museum displays finds from the Mycenaean-era city beneath Naxos Town's northern seafront, dated to the 13th and 12th centuries BC — the same Grotta remains whose acropolis may well have stood on this very hill, long before Marco Sanudo ever arrived.

A Living Heraldic Museum

Wander the Kastro's narrow, marble-paved lanes with your eyes up rather than down, and the district reveals itself as something close to an open-air heraldic archive. Carved marble crests above doorways and lintels throughout the old town mark out the presence of the island's ruling Catholic families across the centuries: Sanudo, the founding ducal house; Crispi, the last dynasty to hold the title of Duke; Della Rocca and Barozzi, two intertwined noble lineages whose shared tower-house is now the Venetian Museum; and Sommaripa, a family whose influence extended to other Cycladic islands including Paros and Andros. These were never merely decorative flourishes; each carved stemma marked genuine property, lineage and standing within a tightly bound aristocratic community that governed Naxos, in various forms, for well over three centuries.

Visiting the Kastro Today

The Kastro sits directly above Naxos Town's harbour and old market street, an easy uphill walk of some ten to fifteen minutes from the waterfront through the narrow lanes of the Bourgos quarter, with the Paraporti gate on the southern side serving as the natural entrance point for most visitors. A public elevator, free to use, carries visitors to the highest point of the complex, arriving near the Avaton 1739 Café, which offers some of the best panoramic views over Chora and the bay available anywhere on the hill — a useful shortcut for anyone who would rather save their legs for exploring the lanes themselves rather than the climb.

Because the Kastro remains a genuinely lived-in neighbourhood, a visit here has a different rhythm from Naxos's excavated archaeological sites: there is no single ticketed entrance or closing time for the district as a whole, though its individual museums — the Archaeological Museum, the Della Rocca-Barozzi Venetian Museum, and the Catholic Cathedral itself — each keep their own opening hours, worth checking locally before a visit. Many of the mansions along its lanes remain private homes, still belonging in some cases to descendants of the original Venetian and Catholic families, alongside others that have been converted into shops, galleries and cafés; a respectful, unhurried walk, rather than a checklist of sights, tends to be the most rewarding way to take the district in.

Nearby: The Centre of Naxos's Historical Web

Few single locations on the island connect as many of its historical threads as the Kastro. The Portara sits a short walk below, its stone very possibly related to the Kastro's own walls; the ancient and medieval remains of Grotta lie along the seafront directly beneath the hill the Kastro occupies; and the Archaeological Museum inside the Kastro itself houses material relevant to nearly every other site in this series, from Early Cycladic figurines to Mycenaean-era finds from Aplomata and Kamini. For anyone working through Naxos's archaeological and historical landmarks in sequence, the Kastro functions less as one more site on the list and more as the hub connecting nearly all of them.

Most of the sites in this series ask a visitor to imagine a vanished world from what remains of it — a doorway with no temple, a statue with no god's name attached, a city glimpsed through glass beneath a modern square. The Kastro asks something different: to walk through a world that, in its own quiet way, never actually left. Eight hundred years after Marco Sanudo first raised these walls over an even older hill, people still live behind them, still climb the same worn marble steps, still keep house under crests carved by their own ancestors. Very few medieval citadels anywhere in Europe can say the same.