Château d'If

François I, King of France, came to Marseille in 1516 to meet Pope Leo X. Eyeing the island of If in the harbour, he recognised its strategic position and ordered a fortress built there. Construction ran from roughly 1524 to 1531, producing a three-tower keep that was militarily effective but, in the end, never tested in battle — no naval attack on Marseille required it. The château's career as a defensive outpost lasted barely a generation before it was converted to a prison in 1580, a role it would hold for over 300 years.

The château's most prominent historical prisoner was Nicolas Fouquet, Louis XIV's Superintendent of Finances, arrested in 1661 and briefly held here before transfer to a permanent cell. Among the most numerous inmates were Huguenots — Protestant dissenters confined in the lower dungeons during the Wars of Religion and their aftermath. A legend attached itself to Château d'If concerning the 'Man in the Iron Mask', the mysterious prisoner whose identity was concealed; though historians now generally place him at the Fortress of Pignerol, the association with Château d'If proved irresistible to literature.

The château ceased functioning as a prison in 1890 and was classified as a national monument. For most of the twentieth century it was progressively restored. Since 1890 its most effective guardian has been literature: Dumas brought more visitors here than any military history could. The Centre des Monuments Nationaux now manages the site, and the ferry from the Vieux-Port runs several times a day throughout the year.

Getting there: The only way to reach Château d'If is by ferry from Marseille's Vieux-Port (Quai des Belges). The crossing takes approximately 15 minutes and costs around €12–18 for a round-trip ticket, depending on the operator. Monument entry (purchased separately) costs approximately €6. Ferries run throughout the day — hourly in summer, less frequently in winter. In July and August, book your ferry in advance: boats fill quickly and the next departure may be two hours away.

What to see: The interior is compact but atmospheric. The central courtyard, the small chapels in the towers, the dimly lit cell blocks, and the two cells labelled for Edmond Dantès and Abbé Faria are the main draws. The ramparts above offer the finest views — Marseille to the east, the Calanques to the south, open sea to the west. Allow 90 minutes inside the fortress and use the ferry journey back to photograph the château from the water at its best angle.

Practical advice: There is no food or shade available on the island. Bring water and sunscreen — the limestone walls reflect heat intensely in summer. Go at opening time or take the last afternoon ferry to avoid the worst of the midday crowds. In winter, the mistral wind can make the sea rough and the island cold; always check weather and ferry conditions before setting out.