The Cistercian Abbaye de Noirlac, founded in 1136, is a fine example of medieval monastic architecture. The chapter house, where the monks’ daily assemblies were held, and the cellier, where the lay brothers were in charge of the food, wine and grain stores, were built in plain but elegant style. The cloisters, with their graceful arches and decorated capitals, date from the 13th and 14th centuries, which was a less severe period.
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.