Saint-Martin-de-Ré, on the Ré island, was first fortified in the early 17th century, when Richelieu'had a bastioned'citadel'built there. The citadel withstood a four-month siege from English forces in 1627, but was demolished soon afterwards. In 1674, concerns were raised over the security of the new naval base at Rochefort and the Ré island became strategically important. Vauban'was sent there to overhaul the island's defences. He drew up plans for a new citadel at Saint-Martin and a bastioned enceinte enclosing the town. The work was essentially complete by 1685, but improvements were made well into the 18th century. The defences of the town and citadel are intact even today and remain one of the best examples of Vauban's 'first system' fortifications.
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