|région: Centre-Val de Loire|
|département: 28, Eure-et-Loir|
Châteaudun is situated at an elevation of 252 m on the river Loir, a tributary of the river Sarthe, in the département Eure-et-Loire, about 44 km southwest of seat of the préfecture, Chartres. It is a sous-préfecture of the department. The municipality of Châteaudun has a population of about 13,100 (2018).
During the Middle Ages, Châteaudun was owned by the counts of Blois who installed the viscounts of Châteaudun here. in the 15th century it was the capital of the county of Dunois, which emerged from the vice-county of Ch$acirc;teaudun. After a large fire in 1723, the historic town centre was rebuilt in Baroque style by the architect Jules Hardouin-Mansart. During the Franco-Prussian War, the city was attacked at the Battle of Châteaudun. On 18 October 1870, Prussian troops captured the city. It was severely damaged in the subsequent house-to-house battle with the Franc tireurs. Many houses were deliberately set on fire even after the fighting ended.
Châteaudun castle is one of the earliest examples of Renaissance architecture in France. The structure was erected
in a strategically favorable position on a rock above the Loir valley. The oldest part of the caste, the keep, was built around 1180. In 1452–1459
it was transformed into a residence by adding the main building and chapel in Gothic style. The north wing was added until 1518 by the dukes of Longuevlile,
marking the transition between the flamboyant Gothic art and the early Renaissance. In 1694 the castle returned to the dukes of Luynes. The castle, half
abandoned by its owners, served as a refuge for the inhabitants of Châteaudun after the fire which ravaged the city in 1723. During the French
Revolution, the chapel was ransacked and the buildings were used as barracks. The first restorations were undertaken in 1866. The castle was again
damaged by the Prussians during the battle of Châteaudun in 1870. In 1938, the castle was acquired by the State, which began its restoration. The
explosion of the bridge in 1944 destabilized the upper parts of the monument, which could nevertheless be straightened without dismantling.
The castle, which is perfectly preserved, is managed by the Centre des monuments nationeaux. Since 1918 it is classified as a national monument.