Château de Cambiaire was built in the 14th century in the town of Saint-Étienne-Vallée-Française. It is a quadrangular building with a round tower at three of its corners and a square tower at the northwest corner. It consists of three wings around a courtyard on the west side by a battlements surrounding wall pierced by a gate. The great crenellated tower, which dungeon office, is crowned on its summit terrace of a watchtower with a roof shaped pepper shakers. This square building built shale stone mixed with white quartz is the oldest. It has three levels, the first two date from the 14th century, the last level and the spiral staircase from a raising of the late 15th century.
This tower seems more ostentatious than most military as much as the castle was never the castle of Saint-Etienne. One of the ground pavement dwelling is probably contemporary dungeon. The others are the result of rearrangements of the modern era and those of the late nineteenth century and finally repairs arising out the 1944 fire. A park of chestnut trees and cedars surrounds the castle. There is a replica of the Lourdes grotto and a chapel dating back to 1875 in neo-Gothic style.
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.