In the heart of Sant Francesc Xavier, the island's capital, this 18th-century fortress-church presides over the square with its whitewashed walls, austere and almost without openings. Blessed in 1738, it was designed with a defensive purpose against pirate attacks: it still preserves the iron-clad door with its loophole and the barrel vault built to withstand artillery. Declared a Site of Cultural Interest in 1996, it remains the heart of village life, surrounded by terraces and street markets. An easy, central visit, ideal early in the morning or at sunset, when the light softens the whiteness of its walls.