Old Fortress of Corfu

The Old Fortress of Corfu — Palaio Frourio in Greek, Fortezza Vecchia to the Venetians who shaped its present form — stands on a rocky double-peaked promontory east of Corfu Town, separated from the mainland by a seawater channel (the Contrafossa) cut by Venetian engineers in the 16th century. It is simultaneously one of the most visually striking sites in the Ionian Islands — the twin summits rising directly from the sea, with towers, bastions, and the Church of St. George visible from the open water — and one of the most historically layered. Records mention a Byzantine kastro at this location from as early as the 6th century AD; what followed was Angevin, then Venetian, then French and British rule, and finally the Greek state from 1864: the Old Fortress compresses a millennium of Mediterranean military and political history into a single limestone promontory.

The Venetian period dominates the physical fabric of the fortress, and it defines Corfu's strategic significance. Venice acquired Corfu in 1386 — the Corfiots offered submission to avoid Genoese control — and immediately recognised the island's position: Corfu lies at the entrance to the Adriatic, the maritime highway that supplied Venice's commercial empire along both coasts of the Adriatic and into the Aegean. Whoever controls Corfu controls whether the Adriatic is open or closed to naval traffic, and for 411 years Venice dedicated substantial resources to ensuring the answer was Venice. The Venetians dredged the Contrafossa to make the eastern promontory effectively an island within an island — a citadel that could hold even if the outer town and walls fell — constructed the inner sea gate (the principal Venetian entrance, still the most atmospheric approach to the fortress), and erected the two main towers on the double summit: the Castel a Terra (land castle, approximately 40 metres above sea level) and the Castel a Mar (sea castle, approximately 5.6 metres above sea level).

The fortress was tested repeatedly, and the Venetian defences held. The Ottoman threat was constant: the Venetians and Ottomans fought continuously for control of the eastern Mediterranean through the 15th and 16th centuries. Corfu withstood Ottoman attacks in 1431 and 1571 — the same year the Ottomans destroyed Cyprus and were stopped at the Battle of Lepanto just off the Greek mainland. The most dramatic siege came in 1716, when a 33,000-strong Ottoman force landed on Corfu and laid siege to the fortress for six weeks. The Corfiots credit their miraculous deliverance to St. Spyridon, the island's patron saint, who appears in devotional paintings from the period holding a torch in the moment of the Turkish retreat. The historical record shows the Venetians called for reinforcements, a relief force arrived, and the Ottomans withdrew — but the Corfiots' interpretation of the events is preserved in the St. Spyridon Church in the old town and in the annual celebration of the island's four major festivals honouring the saint.

The British presence (1814–1864, the United States of the Ionian Islands under British protection) added the fortress's most architecturally incongruous element: the Church of St. George, built in 1840 in the Doric Greek Revival style that was fashionable in Britain for colonial public buildings during the Regency and early Victorian periods. It is a fully-formed classical temple, with columns, pediment, and portico, standing against Venetian battlements in a visual collision that is absurd in theory and oddly compelling in practice. The British also built barracks, stores, and a lighthouse on the outer promontory, converting a Venetian military citadel into a combination garrison town and strategic naval base for the Mediterranean Fleet.

The Ionian Islands were ceded to Greece under the Treaty of London in 1864. The fortress passed to the Greek military and has had periods of active military use and archaeological management; since the UNESCO inscription of Corfu Old Town in 2007, the Old Fortress has been managed primarily as a heritage site and tourist attraction, with the Byzantine museum as its principal indoor exhibit.

The UNESCO inscription itself covers the Old Town of Corfu as a whole — the Old Fortress, the New Fortress (on the western headland, Venetian construction of the 16th century, also visitable), and the Venetian-planned street network of the old town, with its distinctive arcaded streets (the Liston, modelled on the Rue de Rivoli in Paris, built during the French period 1807–1814), the British-era Esplanade, and the surviving Orthodox churches. The inscription recognises the ensemble as an exceptional Venetian urban planning achievement and an unusually complete example of a Venetian provincial capital preserved largely intact.

The GYG guided tour (t607779, 4.9★, 7 reviews, ~$86, 2.5 hours) covers both the Old Fortress and the Corfu Old Town together, providing the connective tissue between the fortress and the city that makes both legible as parts of a single Venetian urban system. The English-speaking guide contextualises the Contrafossa, the siege history, the British architectural additions, and the relationship between the Orthodox religious culture and the Venetian political framework that preserved it. Basic independent entry to the fortress costs €6.

For more fortresses in Greece, [Palamidi Fortress](/castles/greece/palamidi-fortress) (Nafplio, Peloponnese — a Venetian fortress of the same period, with a similar 1716 construction date) and [Acrocorinth](/castles/greece/acrocorinth) (ancient citadel above Corinth, with medieval Frankish and Ottoman layers) are strong comparisons from the mainland — a ferry and a long drive from Corfu, not geographically nearby, but the most useful same-country comparators for a Venetian-period fortress visitor.