Vesterø Søndre Church was built around 1250 by monks of Vitskøl monastery. The tiptych dates from around 1475. The arches are decorated with beautifully with murals depicting the Three Wise Men (made around 1510 by Sæby Workshop).
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.