Schauwenburg Castle has a history dating back to the Middle Ages when, according to historical references from the early 13th century, the Lords of Bertrange occupied a fortified castle. Today's building originated in the 16th century as testified by the Renaissance windows on the eastern and northern wings, the façade being completed in 1710. Around 1780, the d'Huart family who lived in the castle found the facilities too small and constructed a larger building, the Château de Colnet d'Huart, in the vicinity.
Over the years, the Schauwenburg Castle has had many different owners and has been used for a variety of purposes. Since 2008, it has temporarily housed the Commune's administrative offices and served as the town hall.
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.