Castillo De Santiago

Sanlúcar de Barrameda, Spain, Spain

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Castillo de Santiago in Sanlúcar de Barrameda, Spain, is a Gothic-medieval fortress built between 1477 and 1478 by Enrique Pérez de Guzmán, the II Duke of Medina Sidonia, to defend the Guadalquivir River's mouth and bank. This quadrangular castle, with corner towers and a standout hexagonal Keep Tower where Queen Isabella the Catholic reportedly first saw the sea, hosted the Catholic Monarchs that same year and later served as the Dukes' residence, barracks, prison, hospital, and French troops' quarters during the War of Independence. Though armed with artillery until the early 18th century, it lost strategic value as the river receded, faced ruin by century's end, and underwent 19th-century repairs while passing to the Spanish Crown in 1645.