Castle of Zafra, Guadalajara province, Spain

Perched atop a sandstone outcrop high in the Sierra de Caldereros stands the Castle of Zafra. When the Christian kingdoms of northern Spain took the region from its Moorish defenders in the 12th century, they built this castle on the site of an older fortress to defend the borderland between the two powers. Over the years, it withstood countless battles of the Reconquista—the military campaigns waged by Christian kingdoms against Muslim rule in Spain—as well as in the Castilian Civil War of the 14th century.
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