Château des Ducs d'Alençon

This medieval fortress dates from the 12th century when Henry I of England built a massive Norman keep here in 1113. The castle served as the seat of the Dukes of Alençon and was largely rebuilt between 1361 and 1414 by Counts Pierre II and Duke Jean I. Its most famous resident was Marguerite de Navarre, sister of King Francis I, who transformed the castle into a Renaissance cultural salon in the early 16th century. Much of the fortress was destroyed in 1592 by order of King Henry IV. The castle then served as Alençon's prison from 1804 until 2010. Today only the exterior can be viewed, including the 14th-century Tour Couronnée (Crowned Tower) and the entrance pavilion flanked by twin round towers. The former prison courtyard has been converted into Parc Simone Veil, a public park offering views of the medieval walls and towers from ground level.