The existence of a fortification at the site of Mehun-sur-Yèvre dates from antiquity. The major remains are of the early 13th century and the later 14th century. The present standing ruins date from a castle founded under the Courtenays after 1209. This fortress was transformed into a princely residence by John, Duke of Berry in 1367. Largely ruined in the 18th century the castle represented an excellent example of late Gothic architecture and early Renaissance architecture. Charles VII of France, died in the castle on July 22, 1461.
The castle is built on a trapezoid plan, and originally had a tall cylindrical tower at each corner and a rectangular tower in the middle of one of the long sides. An entrance was formed in the wall between two of the towers. One tower (12m diameter) was much larger than the others (8m) and served as the keep. The keep and the west tower still stand to their full height, each capped with intricate defensive machicolations. Manuscript illustrations indicate that the castle also had a large chapel above the principal entrance.
References:Bomarsund fortress and garrison was built in 1832-1854 by Russian Empire to defence Åland Islands against enemies. British and French fleet attacked against it during the Crimean War in 1854. After a week of fighting the British stormed the remaining fort. Anglo-French forces destroyed it totally after battle. In the Treaty of Paris 1856, the entire Åland Islands were demilitarized, which is a status that has been preserved until this day.
Nowadays there are some ruins left and fortress area is open for visitors.